font settings

Font Size: Large | Normal | Small
Font Face: Verdana | Geneva | Georgia

Amniota

(Series)

Overview

[ Back to top ]

The amniotes are a group of vertebrates that have a terrestrially adapted egg. They include mammals, birds and reptiles, as well as their fossil ancestors. Amniote embryos, whether laid as eggs or carried by the female, are protected and aided by several extensive membranes. In humans, these membranes include the amniotic sac that surrounds the fetus. These embryonic membranes, and the lack of a larval stage, distinguish amniotes from tetrapod amphibians.1]

The first amniotes, which resembled small lizards, probably evolved 340 million years ago (Casineria). Their eggs could survive out of the water, allowing amniotes to branch out into drier environments. The eggs could also "breathe" and cope with waste, allowing the eggs and the amniotes themselves to evolve into larger forms. The amniotes spread across the globe and became the dominant land vertebrates. Very early in their history the amniotes split into two main lines. The oldest known fossil synapsid is Protoclepsydrops from about 320 million years ago, while the oldest known sauropsid is probably Paleothyris, in the order Captorhinida, from the Middle Pennsylvanian epoch (ca. 306-312 million years ago).

Description

[ Back to top ]

Amniotes can be characterized in part by embryonic development that includes the formation of several extensive membranes, the amnion, chorion, and allantois. Amniotes develop directly into a (typically) terrestrial form with limbs and a thick stratified epithelium, rather than first entering a feeding larval tadpole stage followed by metamorphosis as in amphibians. In amniotes the transition from a two-layered periderm to cornified epithelium is triggered by thyroid hormone during embryonic development, rather than metamorphosis.[2] The unique embryonic features of amniotes may reflect specializations of eggs to survive drier environments, or the massive size and yolk content of eggs evolved for direct development to a larger size.

Anatomy of an amniotic egg
1. Eggshell
2. Outer membrane
3. Inner membrane
4. Chalaza
5. Exterior albumen (outer thin albumen)
6. Middle albumen (inner thick albumen)
7. Vitelline membrane
8. Nucleus of Pander
9. Germinal disk (blastoderm)
10. Yellow yolk
11. White yolk
12. Internal albumen
13. Chalaza
14. Air cell
15. Cuticula

Features of amniotes evolved for survival on land include a sturdy but porous leathery or hard eggshell and an allantois evolved to facilitate respiration while providing a reservoir for disposal of wastes. Their kidneys and large intestines are also well-suited to water retention. Most mammals do not lay eggs, but corresponding structures may be found inside the placenta.

The first amniotes, such as Casineria kiddi, which lived about 340 million years ago, resembled small lizards. Their eggs were small and covered with a membrane, not a hard shell like most modern amniote eggs. Although some modern amphibians lay eggs on land, with or without significant protection, they all lack advanced traits like an amnion. This kind of egg only became possible with internal fertilization. The outer membrane, a soft shell, evolved as a protection against the harsher environments on land, as species evolved to lay their eggs on land where they were safer than in the water. One can assume the ancestors of the amniotes laid their eggs in moist places, as such modest-sized animals would not have difficulty finding depressions under fallen logs or other suitable places in the ancient forests, and dry conditions were probably not the main reason why the soft shell emerged.[3]

In fish and amphibians there is only one inner membrane, also called an embryonic membrane. In amniotes the inner anatomy of the egg has evolved further and new structures have developed to take care of the gas exchanges between the embryo and the atmosphere, as well as dealing with the waste problems. In order to grow a thicker and tougher shell new ways to supply the embryo with oxygen had to be developed as diffusion alone was not enough. After the egg had developed these structures, further sophistication allowed the amniotes to lay much bigger eggs in much drier habitats. Bigger eggs allowed for bigger offspring and bigger adults could produce bigger eggs, which meant that the amniotes developed the opportunity to grow bigger than their ancestors. Real growth was not possible, however, until they stopped relying on small invertebrates as their main food source and started to eat plants or other vertebrates, or returned to the water. New habits and heavier bodies meant further evolution for the amniotes, both in behavior and anatomy.

There are three main lines of amniotes, which may be distinguished by the structure of the skull and in particular the number of temporal fenestrae (openings) behind the eye. In anapsids (turtles) there are none, in synapsids (mammals and their extinct relatives) there is one, and in most diapsids (non-anapsid reptiles, dinosaurs, and birds) there are two.

The skeletal remains of amniotes can be identified by their having at least two pairs of sacral ribs, a sternum in the pectoral girdle (some amniotes have lost it) and an astragalus bone in the ankle.

Definition and Classification

[ Back to top ]

Amniota was first formally described by embryologist Ernst Haeckel in 1866 on the presence of the amnion, hence the name. A problem with this definition is that the trait (apomorphy) in question does not fossilize, and the status of fossil forms has to be inferred from other traits. Thus Jacques Gauthier and colleagues redefined Amniota in 1988 as "the most recent common ancestor of extant mammals and reptiles, and all its descendants".[4] Gauthiers definition being node-based, the group under his definition has a slightly different content than than the group defined as biological amniotes (apomorphy-based clade).

Traditional Classification

Classifications of the amniotes have traditionally recognised three classes based on major traits and physiology:

This rather orderly scheme is the one most commonly found in popular and basic scientific works. It has come under critique from cladistics, as the class Reptilia is paraphyletic, that is, it has given rise to two other classes not included in Reptilia.

Phylogenetic Classification

With the advent of cladistics, some researchers have attempted to establish new classes, based on phylogeny, but disregarding the physiological and anatomical unity of the groups. One such classification, by Michael Benton, is presented in simplified form below.[5]

Cladogram of Amniotes

The cladogram presented here illustrates the phylogeny (family tree) of amniotes, and follows a simplified version of the relationships found by Laurin & Reisz (1995).[6] The cladogram covers the group as defines under Gauthier's definition.

Photos

[ Back to top ]

Taxonomy

[ Back to top ]

The Series Amniota is a member of the Parvorder Accipitrida. Here is the complete "parentage" of Amniota:

The Series Amniota is further organized into finer groupings including:

Families

[ Back to top ]

Abderitidae

[more]

Abelisauridae

[more]

Abrocomidae

Chinchilla rats are members of the family Abrocomidae. They resemble in appearance, with a similar soft fur and silvery-grey color, but have a body-structure more like a short-tailed rat. They are social, tunnel-dwelling animals, and live in the Andes Mountains of South America. They are probably herbivorous, although this is not clear. [more]

Acanthisittidae

The New Zealand wrens, Acanthisittidae, are a of tiny passerines endemic to New Zealand. They were represented by six known species in four or five genera, although only two species survive in two genera today. [more]

Accipitridae

The Accipitridae is one of the two major within the order Accipitriformes (the diurnal birds of prey). Many well-known birds, such as hawks, eagles, kites, harriers and Old World vultures are included in this group. The Osprey is usually placed in a separate family (Pandionidae), as is the Secretary bird (Sagittariidae), and the New World vultures are also usually now regarded as a separate family or order. Karyotype data indicated that the accipitrids hitherto analysed are indeed a distinct monophyletic group, but whether this group should be considered a family of the Falconiformes or one or several order(s) on their own is a matter of taste. [more]

Acrobatidae

Acrobatidae is a small family of marsupials containing two genera, each with a single species, the Feathertail Glider (Acrobates pygmaeus) from Australia and Feather-tailed Possum (Distoechurus pennatus) from New Guinea. [more]

Acrochordidae

The Acrochordidae are a family created for the genus Acrochordus. This is a group of primitive snakes found in Australia and Indonesia. Currently, 3 species are recognized. [more]

Acrodelphinidae

[more]

Adapidae

[more]

Adapisoriculidae

[more]

Aegithalidae

The long-tailed tits or bushtits, Aegithalidae, are a family of small birds. The family contains 13 species in four genera. [more]

Aegothelidae

Owlet-nightjars are small birds related to the nightjars and frogmouths. Most are native to New Guinea, but some species extend to Australia, the Moluccas, and New Caledonia. There is a single monotypic family Aegothelidae with the genus Aegotheles. [more]

Aepyornithidae

[more]

Afrotarsiidae

[more]

Agamidae

Agamids, of the family Agamidae, include more than 300 species in Africa, Asia, Australia, and a few in Southern Europe. Phylogenetically they may be sister to the Iguanidae, and have a similar appearance. Agamids usually have well-developed, strong legs. Their tails cannot be shed and regenerated like those of geckoes, though a certain amount of regeneration is observed in some[citation needed]. Many agamid species are capable of limited change of their colors[citation needed]. They inhabit warm environments, ranging from hot deserts to tropical rainforests. [more]

Agriochoeridae

[more]

Alaudidae

Larks are birds of the family Alaudidae. All species occur in the Old World, including northern and eastern Australia; only one, the Shore Lark, has spread to North America, where it is called the Horned Lark. Habitats vary widely, but many species live in dry regions. [more]

Alcedinidae

The river kingfishers or Alcedinidae, are one of the three of bird in the kingfisher group. The Alcedinidae once included all kingfishers, before the widespread recognition of Halcyonidae (tree-kingfishers) and Cerylidae (water-kingfishers). [more]

Alligatoridae

[more]

Amphicyonidae

Amphicyonidae is an extinct of large terrestrial carnivores belonging to the suborder Caniformia (meaning "dog-like") and which inhabited North America from (46.2 Mya) of the Middle Eocene subepoch to the Late Eocene subepoch (33.9 Mya). Amphicyonidae existed for approximately . [more]

Amphilemuridae

[more]

Amphisbaenidae

The Amphisbaenidae are a family of , commonly known as worm lizards. They are found in North and South America, some Caribbean islands, and in sub-Saharan Africa. One primitive and somewhat aberrant genus, Blanus, is native to Europe, and may represent a distinct family. [more]

Anatidae

Anatidae is the biological that includes the ducks, geese and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica and on most of the world's islands and island groups. These are birds that are evolutionarily adapted for swimming, floating on the water surface, and in some cases diving in at least shallow water. (The Magpie-goose is no longer considered to be part of the Anatidae, but is placed in its own family Anseranatidae.) The family contains around 146 species in 40 genera. They are generally herbivorous, and are monogamous breeders. A number of species undertake annual migrations. A few species have been domesticated for agriculture, and many others are hunted for food and recreation. Five species have become extinct since 1600, and many more are threatened with extinction. [more]

Anguidae

The Anguidae is a large and diverse family of lizards native to the northern hemisphere. The group includes the , glass lizards, and alligator lizards, among others. Their closest living relatives are the helodermatid lizards. They have hard osteoderms beneath their scales, and many of the species have reduced or absent limbs, giving them a snake-like appearance, although others are fully limbed. [more]

Anhimidae

The screamers are a small family of , the Anhimidae. For a long time they were thought to be related to the Galliformes because of similar bills, but they are truly related to ducks (family Anatidae), most closely to the Magpie-goose (which some DNA evidence suggests[citation needed] are closer to screamers than to ducks). [more]

Anhingidae

The darters or snake-birds are birds in the family Anhingidae. There are four living species, one of which is near-threatened. The darters are frequently referred to as snake-birds because of their long thin neck, which gives a snake-like appearance when they swim with their bodies submerged. [more]

Aniliidae

The Aniliidae are a family created for the monotypic genus Anilius that contains the species A. scytale, found in South America. This snake possesses a vestigial pelvic girdle that is visible as a pair of cloacal spurs. It is ovoviviparous. The diet consists mainly of amphibians and other reptiles. Currently, two subspecies are recognized, including the typical form described here. [more]

Anniellidae

The family Anniellidae, known as American contains two species in a single genus Anniella: A. pulchra, the California legless lizard, with two subspecies A. p. pulchra and A. p. nigra, and the rare A. geronimensis, the Baja California legless lizard. [more]

Anomaluridae

The Anomaluridae family is a family of found in central Africa. They are known as anomalures or scaly-tailed flying squirrels. There are seven species, classified into three genera. Most are brightly colored. [more]

Anomochilidae

The Anomochilidae, or anomochilids, are a family created for the genus Anomochilus, which currently contains 2 monotypic species. [more]

Anseranatidae

The Magpie-goose, Anseranas semipalmata, is a species found in coastal northern Australia and savannah in southern New Guinea. It is a unique member of the order Anseriformes, and arranged in a family and genus distinct from all other living waterfowl. The Magpie-goose is a resident breeder in northern Australia and in southern New Guinea. [more]

Anthracotheriidae

[more]

Antilocapridae

Antilocapridae is a family of endemic to North America. Their closest extant relatives are the giraffids. Only one species, the pronghorn (Antilocapra americana), is living today; all other members of the family are extinct. The living pronghorn is a small ruminant mammal resembling an antelope. It bears small, forked horns. [more]

Aplodontidae

The Mountain Beaver (Aplodontia rufa) is the most primitive extant . Not to be confused with the North American beaver Castor canadensis, or its relative the Eurasian beaver, Castor fiber., it has several common names including Aplodontia, Boomer, Ground Bear, and Giant Mole. The name Sewellel Beaver comes from sewellel or suwellel, the Chinookan term for a cloak made from its pelts. This species is the only living member of its genus, Aplodontia, and family, Aplodontiidae. [more]

Apodidae

The swifts are a family, Apodidae, of highly aerial . They are superficially similar to swallows but are actually not closely related to those passerine species at all; swifts are in the separate order Apodiformes, which they share with the hummingbirds. The treeswifts are closely related to the true swifts, but form a separate family, the Hemiprocnidae. [more]

Apternodontidae

[more]

Apterygidae

Kiwi are endemic to New Zealand, in the genus Apteryx and family Apterygidae. [more]

Archaeohyracidae

[more]

Archaeopterygidae

[more]

Arctocyonidae

Arctocyonidae Giebel, 1855, is an extinct family of mammals. Included genera like , Arctocyonides, Loxolophus, Chriacus, etc. These animals are thought to be the ancestors of the orders Mesonychia and Cetartiodactyla. [more]

Arctostylopidae

[more]

Ardeidae

The herons are wading in the Ardeidae family.There are so far 64 species in this family. Some are called egrets or bitterns instead of herons. Within the family, all members of the genera Botaurus and Ixobrychus are referred to as bitterns, and - including the Zigzag Heron or Zigzag Bittern - are a monophyletic group within the Ardeidae. However, egrets are not a biologically distinct group from the herons, and tend to be named differently because they are mainly white and/or have decorative plumes. Although egrets have the same build as the larger herons, they tend to be smaller. [more]

Arginbaataridae

[more]

Argyrolagidae

[more]

Armintomyidae

[more]

Arsinoitheriidae

[more]

Astrapotheriidae

[more]

Atelidae

The Atelidae are one of the four of New World monkeys now recognised. Formerly they were included in the family Cebidae. Atelids are general larger monkeys, and the family includes the howler, spider and woolly monkeys. They are found throughout the forested regions of Central and South America, from Mexico to northern Argentina. [more]

Atoposauridae

[more]

Atractaspididae

The Atractaspididae are a of snakes found in Africa and the Middle East. Currently, 12 genera are recognized. [more]

Austrotriconodontidae

[more]

Avimimidae

[more]

Azhdarchidae

[more]

Baenidae

[more]

Balaenidae

Balaenidae is a of mysticete whales that contains two living genera. Commonly called the right whales as it contains mainly right whale species. This name can be confusing, however, since one of the species is the Bowhead Whale, which is different from the right whales. [more]

Balaenopteridae

Rorquals are the largest group of , with nine species in two genera. They include the largest animal that has ever lived, the Blue Whale, which can reach 150 tonnes (170 short tons), and two others that easily pass 50 tonnes (55 short tons); even the smallest of the group, the Northern Minke Whale, reaches 9 tonnes (9.9 short tons). [more]

Baptornithidae

[more]

Barylambdidae

[more]

Baryonychidae

[more]

Barytheriidae

[more]

Basilosauridae

Basilosauridae is of extinct cetaceans lived in tropical seas during the late Eocene. [more]

Bataguridae

Geoemydidae (formerly known as Batagurinae) is the largest and most diverse in the order Testudines (turtles) with about 75 species. It includes the Eurasian pond and river turtles and Neotropical wood turtles. [more]

Bathyergidae

The blesmols, also known as mole rats, or African mole-rats, are burrowing rodents of the family Bathyergidae. They represent a distinct evolution of a subterranean life among rodents much like the of North America, the tuco-tucos in South America, or the fossorial muroids. [more]

Batrachostomidae

The frogmouths are a group of birds related to the nightjars. They are found from India across southern Asia to Australia. [more]

Baurusuchidae

[more]

Bavarisauridae

[more]

Bernissartiidae

[more]

Bipedidae

Bipedidae, are a of amphisbaenians. They are found only in Mexico. Ajolotes are carnivorous, burrowing reptiles, but unlike other species of amphisbaenian, they possess two stubby forelimbs placed far forward on the body. The shovel-like limbs are used to scrape away soil while burrowing through the soil, in a similar manner to a mole. [more]

Boidae

The Boidae are a of non-venomous snakes found in America, Africa, Europe, Asia and some Pacific Islands. Relatively primitive snakes, adults are medium to large in size, with females usually larger than the males. The name is derived from the Latin term bos, meaning "cow", and is based on an old myth that boas pursue cows and suckle them until they are drained to death. Two subfamilies comprising eight genera and 43 species are currently recognized. [more]

Bolodontidae

[more]

Bolosauridae

[more]

Bombycillidae

The waxwings form the genus Bombycilla of birds. According to most authorities, this is the only genus placed in the family Bombycillidae. [more]

Bonapartheriidae

[more]

Borhyaenidae

[more]

Bovidae

A bovid is any of almost 140 species of mammals belonging to the family Bovidae. The family is widespread, being native to all continents except South America, Australia and Antarctica, and diverse: members include bison, water buffalo, antelopes, gazelles, sheep, goats, muskox, and domestic cattle. [more]

Brachiosauridae

[more]

Brachypteraciidae

The ground-rollers are a small family of near-passerine birds restricted to Madagascar. They are related to the kingfishers, bee-eaters and rollers. They most resemble the latter group, and are sometimes considered a sub-family of the true rollers. [more]

Bradypodidae

The three-toed sloths are the only members of the Bradypus genus and the Bradypodidae family. There are four living species of three-toed sloths. These are the , the Maned Sloth, the Pale-throated Sloth, and the Pygmy Three-toed Sloth. [more]

Brontotheriidae

Brontotheriidae, also called Titanotheriidae, is a of extinct mammals belonging to the order Perissodactyla, the order that includes horses, rhinos, and tapirs. Superficially they looked rather like rhinoceroses, although they were not true rhinos and are probably most closely related to horses. They lived around 56-34 million years ago, throughout the entirety of the Eocene and into the very earliest part of the Oligocene. [more]

Bucconidae

The puffbirds and their relatives in the family Bucconidae are tropical birds breeding from South America up to Mexico. [more]

Bucerotidae

Hornbills (Bucerotidae) are a of bird found in tropical and sub-tropical Africa and Asia. They are characterized by a long, down-curved bill which is frequently brightly-colored and sometimes has a casque on the upper mandible. Both the common English and the scientific name of the family refer to the shape of the bill, "buceros" being "cow horn" in Greek. In addition, they possess a two-lobed kidney. Hornbills are the only birds in which the first two neck vertebrae (the axis and atlas) are fused together; this probably provides a more stable platform for carrying the bill. The family is omnivorous, feeding on fruit and small animals. They are monogamous breeders nesting in natural cavities in trees and sometimes cliffs. A number of species of hornbill are threatened with extinction, mostly insular species with small ranges. [more]

Bucorvidae

The Ground-hornbills (Bucorvinae) are a subfamily of the family Bucerotidae, with a single genus Bucorvus and two extant species. [more]

Burhinidae

The Stone-curlews or Thick-knees are a group of largely tropical birds,in the family Burhinidae. Despite the group being classed as waders, most species have a preference for arid or semi-arid habitats. They are found worldwide within the tropical zone, with some species also breeding in temperate and Australia. [more]

Burramyidae

The pygmy possums are species of small that together form the marsupial family Burramyidae. There are five extant species of pygmy possum, grouped into two genera. Four of the species are endemic to Australia, with one species also co-occurring in Papua New Guinea and Indonesia. [more]

Caenagnathidae

[more]

Caenolestidae

The Paucituberculata contains the six surviving species of shrew opossum: small, shrew-like marsupials which are confined to the Andes mountains of South America. It is thought that the order diverged from the ancestral marsupial line very early. As recently as 20 million years ago, there were at least seven genera in South America. Today, just three genera remain. They live in inaccessible forest and grassland regions of the High Andes. Insectivores were entirely absent from South America until the Great American Interchange three million years ago, and are currently present only in the northwestern part of the continent. Shrew opossums have lost ground to the these and other placental invaders that fill the same ecological niches. Nevertheless, the ranges of shrew opossums and insectivores overlap broadly. [more]

Cainotheriidae

[more]

Callaeatidae

The small bird family Callaeidae (also named in some sources as Callaeatidae) is to New Zealand. It contains three monotypic genera; of the three species in the family, only two survive and one of them, the Kokako, is an endangered species. A third, the Huia became extinct early in the 20th century. [more]

Callitrichidae

The Callitrichidae (synonym Hapalidae) is one of five of New World monkeys. The family includes several genera, including the marmosets, tamarins, and lion tamarins. For a few years, this group of animals was regarded as a subfamily, called the Callitrichinae, of the Family Cebidae. [more]

Camarasauridae

[more]

Camelidae

Camelids are members of the biological Camelidae, the only living family in the suborder Tylopoda. Camels, dromedaries, llamas, alpacas, vicuñas, and guanacos are in this group. [more]

Canidae

Canidae is the of the dogs; a member of this family is called a canid (). They include wolves, foxes, coyotes, and jackals. The Canidae family is divided into the "true dogs" of the tribe Canini and the "foxes" of the tribe Vulpini. The two species of the basal Caninae are more primitive and do not fit into either tribe. [more]

Caprimulgidae

Nightjars are medium-sized or crepuscular birds with long wings, short legs and very short bills. They are sometimes referred to as goatsuckers from the mistaken belief that they suck milk from goats (the Latin for goatsucker is Caprimulgus). Some New World species are named as nighthawks. Nightjars usually nest on the ground. [more]

Capromyidae

Hutias are moderately large -like rodents of the family Capromyidae that inhabit the Caribbean Islands. They range in size from 20 to 60 cm (7.9 to 24 in), and can weigh up to 7 kg (15 lb). Twenty species of hutia have been identified, and half may be extinct. (Their larger relatives the giant hutias, of the family Heptaxodontidae, are entirely extinct.) They resemble the nutria in some respects and the largest species weigh up to seven kilograms. Tails are present, varying from vestiges to prehensile. They have stout bodies and large heads. Most species are herbivorous, though some consume small animals. Instead of burrowing underground, they nest in trees or rock crevices. Only a few species are common, while others have become endangered. [more]

Captorhinidae

[more]

Carcharodontosauridae

Carcharodontosaurids (from the Carcharodontosauros: "shark-toothed lizards") were a group of carnivorous theropod dinosaurs. In 1931 Ernst Stromer named Carcharodontosauridae as a family, in modern paleontology this name indicates a clade within Carnosauria. Carcharodontosaurids included some of the largest land predators ever known: Giganotosaurus, Mapusaurus, Carcharodontosaurus, and Tyrannotitan all rivaled or exceeded Tyrannosaurus in size. [more]

Carettochelyidae

The Hog-nosed Turtle (Carettochelys insculpta), also known as the Australasian Pig-nose Turtle, Pitted-shelled Turtle, Plateless Turtle or Fly River Turtle, is a of soft-shelled turtle native to freshwater streams, lagoons and rivers of the Northern Territory of Australia and of southern New Guinea. It is a living fossil, being the only living member of the family Carettochelyidae, and the only known species in the subfamily Carettochelyinae and the genus Carettochelys. [more]

Cariamidae

The seriemas are the sole members of the small and ancient family Cariamidae, which is also the sole surviving family of the Cariamae. Once believed to be related to cranes, they are now considered to be more closely related to falcons, parrots and passerines. There are two species: [more]

Carodniidae

[more]

Caroloameghiniidae

[more]

Carpolestidae

Carpolestidae is a family of primate-like that were prevalent in North America and Asia from the mid Paleocene through the early Eocene. Typically, they are characterized by two large upper posterior premolars and one large lower posterior premolar. They weighed about 20-150g, and were about the size of a mouse. Though they come from the order, Plesiadapiformes that may have given rise to the primate order, carpolestids are too specialized and derived to be ancestors of primates. [more]

Caseidae

[more]

Castoridae

The family Castoridae contains the two living species of and their fossil relatives. This was once a highly diverse group of rodents, but is now restricted to a single genus, Castor.
[more]

Casuariidae

The bird family Casuariidae has four surviving members: the three of cassowary, and the only remaining species of Emu. The emus were formerly classified in their own family, Dromaiidae, but are regarded as sufficiently closely related to the cassowaries to be part of the same family. [more]

Caviidae

The Cavy (Caviidae) is a family of rodents native to South America, and including the domestic guinea pig, wild cavies, and the capybara, among other animals. They are found across the continent, in open areas from moist savanna to thorn forests or scrub desert. [more]

Cebochoeridae

[more]

Centropodidae

A coucal is one of about 30 of birds in the cuckoo family. All of them belong in the subfamily Centropodinae and the genus Centropus. Unlike many Old World cuckoos, coucals are not brood parasites. On the other hand they do have their own reproductive peculiarity: all members of the genus are to varying degrees sex-role reversed so that the smaller male provides most of the parental care. At least one coucal species, the Black Coucal, is polyandrous. Some species (Centropus phasianinus) have the male investing more in incubation and parental care. Recent DNA evidence[citation needed] suggests that they should be raised to family status, as Centropodidae. [more]

Ceratopsidae

[more]

Ceratosauridae

[more]

Cercopithecidae

The Old World monkeys or Cercopithecidae are a group of , falling in the superfamily Cercopithecoidea in the clade Catarrhini. The Old World monkeys are native to Africa and Asia today, inhabiting a range of environments from tropical rain forest to savanna, scrubland, and mountainous terrain, and are also known from Europe in the fossil record. However, a (possibly introduced) free-roaming group of monkeys still survives in Gibraltar (Europe) to this day. Old World monkeys include many of the most familiar species of non-human primates such as baboons and macaques. [more]

Certhiidae

The treecreepers are a , Certhiidae, of small passerine birds, widespread in wooded regions of the Northern Hemisphere and sub-Saharan Africa. The family contains ten species in two genera, Certhia and Salpornis. Their plumage is dull-colored, and as their name implies, they climb over the surface of trees in search of food. [more]

Cervidae

Deer are the mammals forming the family Cervidae. They include for example Moose, Red Deer, Reindeer, Roe and Chital. Animals from related families within the order Artiodactyla (even-toed ungulates) are often also considered to be deer – these include muntjac and water deer. Male (and a few female) deer of all species (except the Chinese Water deer who only have short tusks instead) grow and shed new antlers each year – in this they differ from permanently horned animals such as antelope – these are in the same order as deer and may bear a superficial resemblance. The musk deer of Asia and Water Chevrotain (or Mouse Deer) of tropical African and Asian forests are not usually regarded as true deer and form their own families, Moschidae and Tragulidae, respectively. [more]

Cerylidae

The water kingfishers or Cerylidae are one of the three of kingfishers, and are also known as the cerylid kingfishers. All six American species are in this family. [more]

Cetiosauridae

Sauropoda , or the sauropods (), are an or clade of saurischian ("lizard-hipped") dinosaurs. They are notable for the enormous sizes attained by some species, and the group includes many of the largest animals to have ever lived on land. Well-known genera include Apatosaurus (formerly known as Brontosaurus), Brachiosaurus and Diplodocus. Sauropods first appeared in the late Triassic Period, where they somewhat resembled the closely related (and possibly ancestral) group Prosauropoda. By the Late Jurassic (150 million years ago), sauropods were widespread (especially the diplodocids and brachiosaurids). By the Late Cretaceous, those groups had mainly been replaced by the titanosaurs, which had a near-global distribution. However, as with all other non-avian dinosaurs, the titanosaurs died out in the Cretaceous–Tertiary extinction event. Fossilised remains of sauropods have been found on every continent except Antarctica. [more]

Cetotheriidae

[more]

Chalicotheriidae

[more]

Chamaeleonidae

The family Chamaeleonidae are a distinctive and highly specialized of lizards. They are distinguished by their parrot-like zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, and the possession by many of a prehensile tail, crests or horns on their distinctively shaped heads, and the ability of some to change color. Uniquely adapted for climbing and visual hunting, the approximately 160 species of chameleon range from Africa, Madagascar, Spain and Portugal, across south Asia, to Sri Lanka, have been introduced to Hawaii and California, and are found in warm habitats that vary from rain forest to desert conditions. [more]

Champsosauridae

[more]

Chapattimyidae

[more]

Charadriidae

The bird family Charadriidae includes the , dotterels, and lapwings, about 64 to 66 species in all. They are small to medium-sized birds with compact bodies, short, thick necks and long, usually pointed, wings. They range in size from the Collared Plover, at 26 grams and 14 cm (5.5 inches), to the Masked Lapwing, at 368 grams (13 oz) and 35 cm (14 inches). [more]

Cheirogaleidae

Cheirogaleidae is the family of primates that contains the various dwarf and mouse lemurs. Like all other lemurs, cheirogaleids live exclusively on the island of Madagascar. This is the only family in the Cheirogaleoidea superfamily. [more]

Chelidae

The Chelidae are a family of freshwater commonly known as the Austro-American Side-necked Turtles or Snake-necked Turtles. Members are distributed in Australia, New Guinea, and South America. [more]

Cheloniidae

Sea Turtles (superfamily Chelonioidea) inhabit all the world's oceans except the . [more]

Chelydridae

There are two extant of the family Chelydridae: Chelydra serpentina, the Common Snapping Turtle, and its larger relative Macrochelys temminckii, the Alligator Snapping Turtle (although the monotypic Asian genus Platysternon has at times been included in this group). Both are endemic to the Western Hemisphere. [more]

Chinchillidae

The family Chinchillidae contains the , viscachas, and their fossil relatives. They are restricted to southern and western South America, often in association with the Andes. They are large rodents, weighing from 800 g (28 oz) to 8 kg (18 lb), with strong hind legs and large ears. All species have thick, soft fur, which is considered valuable in some species. [more]

Chiniquodontidae

[more]

Chionidae

The sheathbills are a of birds, Chionididae. Classified in the wader order Charadriiformes, the family contains one genus, Chionis, with only two species. They breed on sub-Antarctic islands and the Antarctic Peninsula, and the Snowy Sheathbill migrates to the Falkland Islands and coastal southern South America in the southern winter; they are the only bird family endemic as breeders to the Antarctic region. They are also the only Antarctic birds without webbed feet. [more]

Choeropotamidae

[more]

Chrysochloridae

Golden moles are small, insectivorous burrowing native to southern Africa. They form the family Chrysochloridae, and so are taxonomically distinct from the true moles. The golden moles bear a remarkable resemblance to the marsupial moles of Australia, so much so that, the marsupial/placental divide notwithstanding, they were once thought to be related, possibly because they are very primitive placentals and because of the many mole like specializations. [more]

Ciconiidae

Storks are large, long-legged, long-necked wading with long stout bills, belonging to the family Ciconiidae. They are the only family in the biological order Ciconiiformes, which was once much larger and held a number of families. [more]

Cimolestidae

[more]

Cimolodontidae

[more]

Cimolomyidae

[more]

Cimolopterygidae

[more]

Cinclidae

Dippers are members of the genus Cinclus in the family Cinclidae. They are named for their bobbing or dipping movements. They are unique among passerines for their ability to dive and swim underwater. [more]

Cisticolidae

The Cisticolidae family of small birds is a group of about 110 warblers found mainly in warmer southern regions of the Old World. They are often included within the Old World warbler family Sylviidae. [more]

Climacoceratidae

[more]

Climacteridae

There are 7 of Australasian treecreeper in the passerine bird family Climacteridae. They are medium-small, mostly brown birds with patterning on their underparts, and all are endemic to Australia-New Guinea. They resemble, but are not closely related to, the Holarctic treecreepers. The family is one of several families identified by DNA-DNA hybridisation studies to be part of the Australo-Papuan songbird radiation. There is some molecular support for suggesting that their closest relatives are the large lyrebirds. [more]

Coccyzidae

Coccyzidae is a of birds comprising 18 new world cuckoos, ranging from Canada to Argentina. The family was split from the cuckoo family Cuculidae after considering DNA evidence[citation needed][verification needed]. [more]

Coelophysidae

[more]

Coliidae

The mousebirds are a small group of (possibly ) birds which have no real close affinities to other groups, though they and the parrots and cockatoos (Psittaciformes) may be closer to each other than to other birds. The mousebirds are therefore given order status as Coliiformes. This group is confined to sub-Saharan Africa, and is the only bird order confined entirely to that continent. They had a wider range in prehistoric times and apparently evolved in Europe. [more]

Colubridae

[more]

Columbidae

Pigeons and doves constitute the Columbidae within the order Columbiformes, which include some 300 species of near passerine birds. In general parlance the terms "dove" and "pigeon" are used somewhat interchangeably. In ornithological practice, there is a tendency for "dove" to be used for smaller species and "pigeon" for larger ones, but this is in no way consistently applied, and historically the common names for these birds involve a great deal of variation between the term "dove" and "pigeon." This family occurs worldwide, but the greatest variety is in the Indomalaya and Australasia ecozones. The young doves and pigeons are called "squabs." [more]

Conopophagidae

The gnateaters are a family, Conopophagidae, consisting of ten small passerine species in two genera, which occur in South and Central America. The family was formerly restricted to the gnateater genus Conopophaga; analysis of mtDNA cytochrome b and NADH dehydrogenase subunit 2 sequences (Rice 2005a,b) indicates that the "antpittas" of the genus Pittasoma also belong in this family. The association between this genus and Conopophaga is also supported by traits in their natural history, morphology, and vocalizations (Rice, 2005a). The members of this family are very closely related to the antbirds and less closely to the antpittas and tapaculos. Due to their remote and dim habitat, gnateaters are a little-studied and poorly known family of birds, though they are often sought after by birdwatchers. [more]

Coraciidae

The rollers are an family, Coraciidae, of near passerine birds related to the kingfishers and bee-eaters. The group gets its name from the aerial acrobatics some of these birds perform during courtship or territorial flights. [more]

Cordylidae

Cordylidae is a family of mid-sized lizards that inhabit arid and semi-arid regions in and eastern Africa. T They are commonly known as the Spinytail lizards or Girdle-tailed lizards. [more]

Corvidae

Corvidae is a family of oscine passerine birds that contains the crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs and nutcrackers. The common English name used is corvids (more technically) or the crow family (more informally), and there are over 120 species. The genus Corvus, including the crows and ravens, makes up over a third of the entire family. [more]

Corytophanidae

Corytophanidae is a of lizards also called casque head lizards or helmeted lizards. They typically have well-developed head crests in the shape of a casque. This crest is a sexually dimorphic characteristic, found only on males[citation needed]. There are 9 known species of casque heads from 3 genera. [more]

Cracidae

The chachalacas, guans and curassows are in the family Cracidae. [more]

Craseonycteridae

Kitti's Hog-nosed Bat (Craseonycteris thonglongyai), also known as the bumblebee bat, is a of bat and the only member of the family Craseonycteridae. It occurs in western Thailand and southeast Burma, where it occupies limestone caves along rivers. [more]

Crocodylidae

A crocodile is any belonging to the family Crocodylidae (sometimes classified instead as the subfamily Crocodylinae). The term can also be used more loosely to include all members of the order Crocodilia: i.e. the true crocodiles, the alligators and caimans (family Alligatoridae) and the gharials (family Gavialidae), or even the Crocodylomorpha which includes prehistoric crocodile relatives and ancestors. Crocodiles are large aquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. Crocodiles tend to congregate in freshwater habitats like rivers, lakes, wetlands and sometimes in brackish water. They feed mostly on vertebrates like fish, reptiles, and mammals, sometimes on invertebrates like mollusks and crustaceans, depending on species. They are an ancient lineage, and are believed to have changed little since the time of the dinosaurs. They are believed to be 200 million years old whereas dinosaurs became extinct 65 million years ago; crocodiles survived great extinction events. [more]

Crotaphytidae

[more]

Crotophagidae

The anis (Crotophagidae) are a small of gregarious birds occurring in the Americas. They are part of the cuckoo order Cuculiformes and sometimes placed as a subfamily Crotophaginae within the cuckoo family Cuculidae. [more]

Ctenochasmatidae

[more]

Ctenodactylidae

Gundis ( Ctenodactylidae) are a group of small, stocky rodents found in Africa. They live in rocky deserts across the northern parts of the continent. The family comprises 4 living genera and 5 species (Speke's Gundi, Felou Gundi, Desert Gundi, North African Gundi and Mzab Gundi), as well as numerous extinct genera and species (McKenna and Bell, 1997). They are in the superfamily Ctenodactyloidea. They first came to the notice of western naturalists in Tripoli in 1774 and were given the name 'gundi mice'. [more]

Cuculidae

The cuckoos are a family, Cuculidae, of birds. The order Cuculiformes, in addition to the cuckoos, also includes the turacos (family Musophagidae, sometimes treated as a separate order, Musophagiformes). Some zoologists and taxonomists have also included the unique Hoatzin in the Cuculiformes, but its taxonomy remains in dispute. The cuckoo family, in addition to those species named as such, also includes the roadrunners, koels, malkohas, couas, coucals and anis. The coucals and anis are sometimes separated as distinct families, the Centropodidae and Crotophagidae respectively. [more]

Cyamodontidae

[more]

Cyclopedidae

Silky Anteater or Pygmy Anteater (Cyclopes didactylus) is a of anteater from Central and South America, ranging from extreme southern Mexico south to Brazil and possibly Paraguay. It is the only species in the Cyclopes genus and the Cyclopedidae family. [more]

Cylindrodontidae

[more]

Cylindrophiidae

The Cylindrophiidae are a family containing the genus Cylindrophis found in Asia. These are burrowing snakes and all have checkered black-and-white bellies. Currently, 8 species are recognized and no subspecies. [more]

Cyriacotheriidae

[more]

Dacrytheriidae

[more]

Dalpiazinidae

[more]

Dasypodidae

Armadillos are small mammals, known for having a leathery armor shell. The Dasypodidae are the only surviving family in the order Cingulata, part of the superorder Xenarthra along with the anteaters and sloths. The word armadillo is Spanish for "little armored one". [more]

Dasyproctidae

The Dasyproctidae are a family of large rodents, comprising the agoutis and acouchis. Their fur is a reddish or dark color above, with a paler underside. They are herbivorous, often feeding on ripe fruit that falls from trees. They live in burrows, and, like squirrels, will bury some of their food for later use. [more]

Dasyuridae

The Dasyuridae is a family of native to Australia and New Guinea, including 61 species divided into 15 genera. Many are small and mouse-like, giving them the misnomer marsupial mice, but the group also includes the cat-sized quolls, as well as the Tasmanian Devil. They are found in a wide range of habitats, including grassland, forests, and mountains, and some species are arboreal or semi-aquatic. [more]

Daubentoniidae

The Aye-aye (Daubentonia madagascariensis) is a native to Madagascar that combines rodent-like teeth with a long, thin middle finger to fill the same ecological niche as a woodpecker. It is the world's largest nocturnal primate, and is characterized by its unusual method of finding food; it taps on trees to find grubs, then gnaws holes in the wood and inserts its elongated middle finger to pull the grubs out. The only other animals known to find food in this way is the Striped Possum. From an ecological point of view the Aye-aye fills the niche of a woodpecker as it is capable of penetrating wood to extract the invertebrates within. [more]

Deinotheriidae

Deinotheriidae ("terrible beasts") is a family of prehistoric elephant-like that lived during the Tertiary period, first appearing in Africa, then spreading across southern Asia (Indo-Pakistan) and Europe. During that time they changed very little, apart from growing much larger in size - by the late Miocene they had become the largest land animals of their time. Their most distinctive feature was the downward curving tusks on the lower jaw. [more]

Delphinidae

Oceanic dolphins are the members of the Delphinidae family of . These aquatic mammals are related to whales and porpoises. They are found worldwide, mostly in the shallower seas of the continental shelves. As the name implies, these dolphins tend to be found in the open seas, unlike the river dolphins, although a few species such as the Irrawaddy Dolphin are coastal or riverine. [more]

Deltatheridiidae

[more]

Dendrocygnidae

Dendrocygninae is a of the duck, goose and swan family of birds, Anatidae. In other taxonomical approaches, they are either considered a separate family Dendrocygnidae, or a tribe Dendrocygnini in the goose subfamily Anserinae (e.g. Terres & NAS, 1991). [more]

Dermatemydidae

The Mesoamerican River Turtle (Dermatemys mawii) locally known as the "hickatee" or "tortuga blanca"-(white turtle) is the only in the family Dermatemydidae. It is a nocturnal, aquatic turtle that lives in larger rivers and lakes in Central America, from southern Mexico to northern Honduras. It is considered an endangered species. [more]

Dermochelyidae

The leatherback turtle (Dermochelys coriacea) is the largest of all living and the fourth largest modern reptile behind three crocodilians. It is the only living species in the genus Dermochelys. It can easily be differentiated from other modern sea turtles by its lack of a bony shell. Instead, its carapace is covered by skin and oily flesh. Dermochelys coriacea is the only extant member of the family Dermochelyidae. Instead of teeth the Leatherback turtle has points on the tomium of its upper lip. It also has backwards spines in its throat to help it swallow food. Leatherback turtles can dive to depths as great as 4,200 feet (1,280 metres). [more]

Desmostylidae

[more]

Dibamidae

[more]

Dichobunidae

[more]

Dicynodontidae

[more]

Didelphidae

Didelphimorphia is the of common opossums of the Western Hemisphere. They are commonly also called possums, though that term is also applied to Australian fauna of the suborder Phalangeriformes. The Virginia Opossum is the original animal named opossum. The word comes from Algonquian wapathemwa. Opossums probably diverged from the basic South American marsupials in the late Cretaceous or early Paleocene. A sister group is Paucituberculata (shrew opossums). [more]

Didolodontidae

[more]

Didymoconidae

[more]

Dimylidae

[more]

Dinomyidae

The family Dinomyidae was once a very speciose group of hystricognath rodent, but now contains only a single living species, the Pacarana. The Dinomyidae included among its ranks the largest rodents known to date, the bison-sized Josephoartigasia monesi and the smaller Josephoartigasia magna. It is thought[by whom?] that the dinomyids were able to occupy ecological niches associated with large grazing mammals due to the lack of true ungulates in South America until its later connection to North America. The modern pacarana is only modest[vague] sized, considerably[vague] smaller than the capybara.[citation needed] [more]

Dinornithidae

[more]

Diplodocidae

Diplodocids, or members of the family Diplodocidae ("double beams"), are a group of dinosaurs. The family includes some of the longest creatures ever to walk the earth, including Diplodocus and Supersaurus, which may have reached lengths of up to 34 m (112 ft.), and the gigantic Amphicoelias, known from a single vertebra representing an individual that may have exceeded 40 meters (131 ft) or reached 60 (201 ft). [more]

Dipodidae

The Dipodidae, or dipodids, are a of rodents found across the northern hemisphere. They include the jerboas, jumping mice, and birch mice. Different species are found in grassland, deserts, and forests. They are all capable of saltation (jumping while in a bipedal stance), a feature that is most highly evolved in the desert-dwelling jerboas. [more]

Diprotodontidae

[more]

Dolichosauridae

[more]

Dromornithidae

[more]

Dryolestidae

[more]

Dryosauridae

[more]

Dryptosauridae

[more]

Dsungaripteridae

[more]

Dugongidae

Dugongidae is a in the order of Sirenia. [more]

Dyrosauridae

[more]

Echimyidae

The spiny rats are a group of rodents in the family Echimyidae. They are distributed from central Central America through much of South America. They were also found in the West Indies until the 1800s. Some authorities consider the nutria from southern and central South America to be a part of this family. [more]

Ektopodontidae

[more]

Elapidae

[more]

Elasmosauridae

[more]

Elephantidae

Elephants are large land of the order Proboscidea and the family Elephantidae. There are three living species: the African Bush Elephant, the African Forest Elephant and the Asian Elephant (also known as the Indian Elephant). Other species have become extinct since the last ice age: the Mammoths, dwarf forms of which may have survived as late as 2,000 BC, being the best-known. Elephants were once classified with other thick-skinned animals in a now invalid order, Pachydermata. [more]

Emballonuridae

The 47 species of sac-winged or sheathtailed bats constitute the Emballonuridae, and can be found in tropical and sub-tropical regions all over the world. Emballonurids include some of the smallest of all bats, and range from 3.5 to 10 cm in body length. They are generally brown or grey, although the ghost bats (genus Diclidurus) are white. [more]

Emydidae

The Emydidae are the largest and most diverse of Testudines. [more]

Endothiodontidae

[more]

Entelodontidae

Entelodonts, sometimes nicknamed Terminator Pigs is an extinct of pig-like omnivores endemic to forests and North America, Europe, and Asia and from the middle Eocene to early Miocene epochs (37.2—16.3 mya), existing for approximately 20.9 million years. [more]

Eocardiidae

[more]

Eomyidae

Eomyidae is a of extinct rodents from North America and Eurasia related to modern day pocket gophers and kangaroo rats. The family includes the earliest known gliding rodent, Eomys (Storch et al., 1996) [more]

Eosimiidae

[more]

Eothyrididae

[more]

Epoicotheriidae

[more]

Equidae

Equidae (sometimes known as the horse family) is the family of horses and related animals, including the extant horses, donkeys, and zebras, and many other species known only from fossils. All extant species are in the genus Equus. Equidae belongs to the order Perissodactyla, which includes the extant tapirs and rhinoceros, and still more fossils. [more]

Erethizontidae

The New World porcupines, or Erethizontidae, are large rodents, distinguished by the spiny covering from which they take their name. They inhabit forests and wooded regions across North America, and into northern South America. Although both the New World and Old World porcupine families belong to the Hystricognathi branch of the vast order Rodentia, they are quite different and are not closely related. [more]

Erinaceidae

Erinaceidae is the only living family in the order of the Erinaceomorpha. It contains the well-known (subfamily Erinaceinae) of Eurasia and Africa and the gymnures or moonrats (subfamily Galericinae) of South-east Asia. This family was once considered part of the order Insectivora, but that polyphyletic order is now considered defunct. [more]

Eubrontidae

[more]

Eurostopodidae

The Eared-nightjars are a small of birds related to nightjars. There are seven species, mainly found in forest and scrub from China to Australia. There is but one genus, Eurostopodus. Previously, they were considered a subfamily Eurostopodinae of the nightjar and nighthawk family Caprimulgidae. [more]

Eurylaimidae

The broadbills are a family of small birds, Eurylaimidae. The Smithornis and Pseudocalyptomena species occur in sub-Saharan Africa; the rest extend from the eastern Himalayas to Sumatra and Borneo. The family possibly also includes the Sapayoa from the Neotropics and the asities from Madagascar. [more]

Eurymylidae

[more]

Eurypygidae

The Sunbittern, Eurypyga helias is a -like bird of tropical regions of the Americas, and the sole member of the family Eurypygidae (sometimes spelled Eurypigidae) and genus Eurypyga. [more]

Falconidae

The falcons and caracaras are around 60 of diurnal birds of prey that comprise the family Falconidae. The family is divided into two subfamiles, Polyborinae, which includes the caracaras and forest falcons, and Falconinae, the falcons, kestrels and falconets. [more]

Felidae

[more]

Ferugliotheriidae

[more]

Florentiamyidae

[more]

Formicariidae

The Formicariidae, formicariids, or ground antbirds are a of smallish passerine birds of subtropical and tropical Central and South America. They are between 10 and 20 cm (4-8 in) in length, and are related to the antbirds, Thamnophilidae, and gnateaters, Conopophagidae. This family contains probably (see below) some 100–120 species in 1 or 2 large and a number of fairly small genera. [more]

Fregatidae

The frigatebirds are a family, Fregatidae, of . There are five species in the single genus Fregata. They are also sometimes called Man of War birds or Pirate birds. Since they are related to the pelicans, the term "frigate pelican" is also a name applied to them. They have long wings, tails and bills and the males have a red gular pouch that is inflated during the breeding season to attract a mate. [more]

Fringillidae

The true finches are birds in the family Fringillidae. They are predominantly seed-eating songbirds. Most are native to Southern Hemisphere, but one subfamily is endemic to the Neotropics, one to the Hawaiian Islands, and one subfamily – monotypic at genus level – is found only in the Palaearctic. The scientific name Fringillidae comes from the Latin word fringilla for the Chaffinch (Fringilla coelebs) – a member of that last subfamily – which is common in Europe. [more]

Furipteridae

Furipteridae is one of the of bats. This familiy contains only two species, the Smokey Bat and the Thumbless Bat. Both are from Central and South America, and are closely related to the bats in the Natalidae and Thyropteridae families. They can be recognized by their reduced and functionless thumbs, enclosed by the wing membranes, and their broad, funnel-shaped ears. There are only two genera in the group, each with a single species. They are insectivorous and can live in many different kinds of environments. They have greyish fur, and a small nose-leaf. Like many bats, they roost in caves. [more]

Furnariidae

Ovenbirds or furnariids are a large family of small passerine bird species found in Central and South America. They form the family Furnariidae. The North American Ovenbird (Seiurus aurocapillus) is a rather distantly related bird, a wood warbler (family Parulidae). [more]

Galbulidae

The jacamars are a , Galbulidae, of near passerine birds from tropical South and Central America, extending up to Mexico. The order contains five genera and 18 species. The family is closely related to the puffbirds, another Neotropical family, and the two families are often separated into their own order away from the Piciformes, instead being placed in the Galbuliformes. They are principally birds of low altitude woodlands and forests, and particularly of forest and edge and canopy. [more]

Gavialidae

Gavialidae is a family of within the order Crocodilia. Gavialidae consists of only two surviving species, the gharial (Gavialis gangeticus) and the false gharial (Tomistoma schlegelii), which are each the sole living representatives of their genera. They are native to India and the Malay peninsula. [more]

Gaviidae

The loons (North America) or divers (UK/Ireland) are a group of aquatic birds found in many parts of and northern Eurasia (Europe, Asia and debatably Africa). All living species of loons are members of one genus (Gavia), family (Gaviidae) and order (Gaviiformes) of their own. [more]

Gekkonidae

Geckos are small to average sized belonging to the family Gekkonidae, found in warm climates throughout the world. Geckos are unique among lizards in their vocalizations, making chirping sounds in social interactions with other geckos. An estimated 2,000 different species of geckos exist worldwide, with many likely yet to be discovered. The name stems from the Indonesian/Javanese word Tokek, inspired by the sound these animals make. The Malay word for gecko is cicak. [more]

Gelocidae

[more]

Geolabididae

[more]

Geomyidae

The pocket gophers are burrowing of the family Geomyidae. These are the "true" gophers, though several ground squirrels of the family Sciuridae are often called gophers as well. The name "pocket gopher" on its own may be used to refer to any of a number of subspecies of the family. [more]

Gerrhosauridae

The Gerrhosauridae is a family of lizards native to Africa and Madagascar. Also known as plated lizards, they live in a range of habitats, from rocky crevices to sand dunes. Their form is variable, with some species having four fully developed limbs, and others with vestigial hind limbs only. Most species are believed to be . [more]

Giraffidae

The giraffids are artiodactyl mammals that share a common ancestor with deer and bovids. The biological family Giraffidae, once a diverse group spread throughout Eurasia and Africa, contains only two living members, the giraffe and the okapi. Both are confined to sub-saharan Africa: the giraffe to the open savannas, and the okapi to the dense rainforest of the Congo. The two species look very different on first sight, but share a number of common features, including a long, dark-colored tongue, lobed canine teeth, and horns covered in skin, called "ossicones". [more]

Glareolidae

Glareolidae is a of birds in the wader suborder Charadri. It contains two distinct groups, the pratincoles and the coursers. The coursers include the atypical Egyptian Plover, Pluvianus aegyptius, which has sometimes been placed in its own family. The family contains 17 species in five genera. [more]

Glasbiidae

[more]

Gliridae

Dormice are of the family Gliridae. (This family is also variously called Myoxidae or Muscardinidae by different taxonomists). Dormice are mostly found in Europe, although some live in Africa and Asia. They are particularly known for their long periods of hibernation. Because only one species of dormouse is native to the British Isles, in everyday English usage "dormouse" usually refers to this species (the Hazel Dormouse) rather than to the family as a whole. [more]

Glyptodontidae

[more]

Glyptopsidae

[more]

Gomphotheriidae

The Gomphotheres are a diverse group of elephant-like animals (proboscideans) that were widespread in North America during the Miocene and Pliocene epochs, 12-1.6 million years ago. Some also lived in parts of Eurasia and Beringia, and following the Great American Interchange, in South America. From about 5 million years ago onwards, they were slowly replaced by modern elephants, but the last South American species did not finally become extinct until possibly as recently as 400 CE. Gomphotheres also survived in Mexico and Central America until the end of the Pleistocene. [more]

Goniopholididae

[more]

Gorgonopsidae

[more]

Grallatoridae

[more]

Groeberiidae

[more]

Gruidae

Cranes are large, long-legged and long-necked of the order Gruiformes, and family Gruidae. Unlike the similar-looking but unrelated herons, cranes fly with necks outstretched, not pulled back. There are representatives of this group on all the continents except Antarctica and South America. [more]

Gymnophthalmidae

Gymnophthalmidae is a of lizards, sometimes known as spectacled lizards or microteiids. They are called 'spectacled' because of their transparent lower eyelids, so they can still see with closed eyes. Like most lizards, but unlike geckos, these eyelids are movable. [more]

Gypsonictopidae

[more]

Hadrosauridae

Hadrosaurids or duck-billed are members of the family Hadrosauridae, and include ornithopods such as Edmontosaurus and Parasaurolophus. They were common herbivores in the Upper Cretaceous Period of what are now Asia, Europe and North America. They are descendants of the Upper Jurassic/Lower Cretaceous iguanodontian dinosaurs and had similar body layout. They were ornithischians. [more]

Hahnodontidae

[more]

Halcyonidae

[more]

Hapalodectidae

[more]

Haplobunodontidae

[more]

Haramiyidae

[more]

Harpyodidae

[more]

Hegetotheriidae

[more]

Helaletidae

[more]

Heliornithidae

The Heliornithidae are a small of tropical birds with webbed lobes on their feet like those of grebes and coots. The family overall are known as finfoots, although one species is known as a Sungrebe. The family is composed of three species in three genera. [more]

Helodermatidae

[more]

Helohyidae

[more]

Hemiprocnidae

The treeswifts or crested swifts are a , Hemiprocnidae, of aerial near passerine birds, closely related to the true swifts. The family contains a single genus, Hemiprocne, with four species. They are distributed from India and South East Asia through Indonesia to New Guinea and the Solomon Islands. [more]

Henricosborniidae

[more]

Heptaxodontidae

The giant hutias are an group of large rodents known from fossil and subfossil material in the West Indies. One species, Amblyrhiza inundata, is estimated to have weighed between 50 and 200 kg (110 and 440 lb), big specimens being as large as an American Black Bear. This is much larger than Capybara, the largest rodent living today, but still much smaller than Josephoartigasia monesi, the largest rodent known. These animals may have persisted into historic times and were probably used as a food source by aboriginal humans. All giant hutias are in a single family Heptaxodontidae, which contains no living species; this grouping seems to be paraphyletic and artificial however. [more]

Herpestidae

Mongoose (plural: mongooses or, rarely, mongeese) is a name for any member of the Herpestidae (although also used for some members of Eupleridae), a family of small, cat-like carnivores. [more]

Herrerasauridae

[more]

Hesperornithidae

[more]

Hippopotamidae

[more]

Hirundinidae

The swallows and martins are a group of birds in the family Hirundinidae which are characterised by their adaptation to aerial feeding. Swallow is used colloquially in Europe as a synonym for the Barn Swallow. [more]

Homalodotheriidae

[more]

Hominidae

The Hominidae (anglicized Hominids, also known as great apes) form a taxonomic , including four extant genera: chimpanzees, gorillas, humans and orangutans. [more]

Hoplocercidae

[more]

Huayangosauridae

[more]

Hyaenidae

The Hyaenidae is a family of order Carnivora. The Hyaenidae family, native to both African and Asian continents, consists of four living species, the Striped Hyena and Brown Hyena (genus Hyaena), the Spotted Hyena (genus Crocuta), and the Aardwolf (genus Proteles). [more]

Hyaenodontidae

Hyaenodontidae (" teeth") is a family of the extinct order Creodonta, which contains several dozen genera. [more]

Hydrochoeridae

[more]

Hyopsodontidae

[more]

Hypertragulidae

[more]

Hyracodontidae

Hyracodontidae is an family of rhinoceroses that evolved during the Eocene epoch and continued into the Miocene. They are typified as having long limbs and having no horns. These animals were initially modest in size and fast moving, having evolved from the smaller rhinocerotoidea during the Late Eocene and Early Oligocene. They later evolved into gigantic forms that included the largest terrestrial mammals (the Indricotheriinae or Paraceratheriinae) ever to have lived. [more]

Hystricidae

The Old World porcupines, or Hystricidae, are large terrestrial , distinguished by the spiny covering from which they take their name. They range over the south of Europe, most of Africa, India, and the Malay Archipelago as far east as Borneo. Although both the Old World and New World porcupine families belong to the Hystricognathi branch of the vast order Rodentia, they are quite different and are not closely related. [more]

Ichthyornithidae

[more]

Idiornithidae

[more]

Iguanidae

The Iguanidae is a family of , composed of iguanas and related species. [more]

Iguanodontidae

Iguanodonts were herbivorous that lived from the mid-Jurassic to Late Cretaceous. Some members include Camptosaurus, Callovosaurus, Iguanodon, and Ouranosaurus. Iguanodonts were one of the first groups of dinosaurs to be found. They are among the best known of the dinosaurs, and include the "duck-billed" hadrosaurs. Iguanodontians were fairly large animals, and some (such as Shantungosaurus, which measured up to 50 ft (15 m) in length and weighed up to 8 tons) approached the largest carnivorous dinosaurs in size. [more]

Ilariidae

[more]

Indicatoridae

Honeyguides, ( Indicatoridae), are near passerine bird species of the order Piciformes. They are also known as indicator birds, or honey birds, although the latter term is also used more narrowly to refer to species of the genus Prodotiscus. They have an Old World tropical distribution, with the greatest number of species in Africa and two in Asia. [more]

Indridae

The Indridae (also spelled Indriidae) are a family of primates. They are medium to large sized lemurs with only four teeth in the toothcomb instead of the usual six. Indriids, like all lemurs, live exclusively on the island of Madagascar. [more]

Iniidae

Iniidae is a of river dolphins containing one living and three extinct genera. [more]

Interatheriidae

[more]

Irenidae

The two fairy-bluebirds are small bird species found in forests and plantations in tropical southern Asia and the Philippines. They are the sole members of the genus Irena and family Irenidae, and are related to the ioras and leafbirds. [more]

Ischyromyidae

[more]

Isectolophidae

[more]

Isotemnidae

[more]

Ivanantoniidae

[more]

Jacanidae

For the Melbourne suburb, see . [more]

Kannemeyeriidae

[more]

Kentriodontidae

[more]

Kermackiidae

[more]

Kinosternidae

Kinosternidae is a of mostly small turtles that includes the mud and musk turtles. The family Kinosternidae contains 25 species within 4 genera, but taxonomic reclassification is an ongoing process so many sources vary on the exact numbers of species and subspecies. They inhabit slow-moving bodies of water, often with soft, muddy bottoms and abundant vegetation. [more]

Kollikodontidae

[more]

Kuehneosauridae

[more]

Kuehneotheriidae

[more]

Lacertidae

Lacertidae is the of the wall lizards, or true lizards, which are native to Europe, Africa, and Asia. The group includes the genus Lacerta, which contains some of the most commonly seen lizard species in Europe. [more]

Lagerpetonidae

[more]

Laniidae

Shrikes are birds of the family Laniidae. The family is composed of thirty one species in three genera. The family name, and that of the largest genus, Lanius, is derived from the Latin word for butcher, and some shrikes were also known as "butcher birds" because of their feeding habits. Several African species are known as fiscals, derived from the Afrikaans term for the hangman, fiskaal. [more]

Lanthanotidae

The earless monitor lizard (Lanthanatus boreneensis) is a semi-aquatic, brown lizard native to northern . It is the only species in the family Lanthanotidae, a group related to the true monitor lizards, as well as to the beaded lizards. [more]

Laredomyidae

[more]

Laridae

Gulls (often informally seagulls) are in the family Laridae. They are most closely related to the terns (family Sternidae) and only distantly related to auks, skimmers, and more distantly to the waders. Until recently, most gulls were placed in the genus Larus, but this arrangement is now known to be polyphyletic, leading to the resurrection of several genera. [more]

Leiosauridae

[more]

Lemuridae

Lemuridae is a of prosimian primates native to Madagascar, and one of four families commonly known as lemurs. These animals were thought to be the evolutionary predecessors of monkeys and apes, but this is no longer considered correct. The family gets its name from the Ancient Roman belief[citation needed] that the animals were ghosts or spirits ('lemures'), because many species are nocturnal. [more]

Leontiniidae

[more]

Leporidae

Leporids are the approximately 50 species of and hares which form the family Leporidae. The leporids, together with the pikas, constitute the Lagomorpha order of mammals. Leporids differ from pikas in having short furry tails, and elongated ears and hind legs. The name leporid is derived from Latin leporis, genitive of lepus, a hare. [more]

Leptictidae

[more]

Leptomerycidae

[more]

Leptosomidae

The Cuckoo-roller, Leptosomus discolor, is the only in the family Leptosomatidae, which is usually considered to be within the order Coraciiformes, which also includes the kingfishers, bee-eaters and rollers. However, the position of this family is not very clear. Morphological evidence has been quoted for a placement within or near to Falconiformes. In the rather comprehensive DNA study by Hackett et al. this is one of only two birds – besides the Hoatzin – of which the position is not clear, although it seems to be at the root of a group that contains the Trogoniformes, Bucerotiformes, Piciformes and Coraciiformes. [more]

Leptotyphlopidae

The Leptotyphlopidae (commonly called Slender Blind Snakes or Thread Snakes) are a of snakes found in North and South America, Africa, and Asia. All are fossorial and adapted to burrowing, feeding on ants and termites. Currently, 2 genera are recognized comprising 87 species. [more]

Limnoscelidae

[more]

Lipotidae

The (: ???; pinyin: báijìtún) (Lipotes vexillifer, Lipotes meaning "left behind", vexillifer "flag bearer") is/was a freshwater dolphin found only in the Yangtze River in China. Nicknamed "Goddess of the Yangtze" (simplified Chinese: ????; traditional Chinese: ????; pinyin: Cháng Jiang nushén) in China, the dolphin was also called Chinese River Dolphin, Yangtze River Dolphin, Whitefin Dolphin and Yangtze Dolphin. It is not to be confused with the Chinese White Dolphin (simplified Chinese: ?????; traditional Chinese: ?????; pinyin: Zhonghuá bái haitún). The 2007 IUCN Red List classifies the Baiji as extinct. [more]

Llanocetidae

[more]

Lophialetidae

[more]

Lophiodontidae

[more]

Lophiomerycidae

[more]

Loridae

Lorisidae (or sometimes Loridae) is a family of primates. The lorids are all slim arboreal animals and include the lorises, pottos and angwantibos. Lorids live in tropical, central Africa as well as in south and southeast Asia. [more]

Loxocemidae

The Loxocemidae are a family of snakes created for the monotypic genus Loxocemus that contains the species L. bicolor found in Mexico. No subspecies are currently recognized. [more]

Lybiidae

The Lybiidae is a family containing the African barbets. They were usually united with their American and Asian relatives in the Capitonidae for quite some time, but this has been confirmed to be limited to the main American lineage[citation needed]. There are 42 species ranging from the type genus Lybius of forest interior to the tinkerbirds (Pogoniulus) of forest and scrubland. They are found throughout sub-Saharan Africa, with the exception of the far south-west of South Africa. [more]

Lystrosauridae

[more]

Macraucheniidae

[more]

Macrocephalosauridae

[more]

Macropodidae

Macropods are belonging to the family Macropodidae, which includes kangaroos, wallabies, tree-kangaroos, pademelons, and several others. Before European settlement, there were about 53 species of Macropods. Six species have since become extinct. Another 11 species have been greatly reduced in numbers. Other species (e.g. Simosthenurus, Propleopus, Macropus titan) went extinct after the Australian Aborigines arrived and before Europeans arrived. [more]

Macroscelididae

Elephant shrews or jumping shrews are small mammals native to Africa, belonging to the Macroscelididae family, in the order Macroscelidea. Their traditional common English name comes from a fancied resemblance between their long noses and the trunk of an elephant, and an assumed relationship with the true shrews (family Soricidae) in the order Insectivora. As it has become plain that the elephant shrews are unrelated to the shrews, the biologist Jonathan Kingdon has proposed that they instead be called sengis, a term derived from the Bantu languages of Africa. [more]

Madtsoiidae

[more]

Maluridae

The Maluridae are a of small, insectivorous passerine birds endemic to Australia and New Guinea. Commonly known as wrens, they are unrelated to the true wrens of the Northern Hemisphere. The family includes 14 species of fairy-wren, 3 emu-wrens, and 10 grasswrens. [more]

Mammalodontidae

[more]

Mammutidae

Mammutidae, also known as , was a family of prehistorical proboscideans that lived between the miocene to pleistocene or holocene. [more]

Manidae

A pangolin , also scaly anteater or trenggiling, is a of the order Pholidota. There is only one extant family (Manidae) and one genus (Manis) of pangolins, comprising eight species. There are also a number of extinct taxa. Pangolins have large keratin scales covering their skin and are the only mammals with this adaptation. They are found in tropical regions of Africa and Asia. The name "pangolin" derives from the Malay word pengguling ("something that rolls up"). Pangolins are nocturnal animals, using their well-developed sense of smell to find insects. The long-tailed pangolin is also active by day. Pangolins spend most of the daytime sleeping, curled up into a ball. [more]

Megadermatidae

Megadermatidae, or False Vampire Bats, are a family of found from central Africa, eastwards through southern Asia, and into Australia. They are relatively large bats, ranging from 6.5 cm to 14 cm in head-body length. They have large eyes, very large ears and a prominent nose-leaf. They have a wide membrane between the hind legs, but no tail. Many species are a drab brown in color, but some are white, bluish-grey or even olive-green, helping to camouflage them against their preferred roosting environments. They are primarily insectivorous, but will also eat a wide range of small vertebrates. [more]

Megalaimidae

A family of comprising the Asian barbets, the Megalaimidae were once united with all other barbets in the Capitonidae (Short & Horne 2002) but they have turned out to be distinct[citation needed]. There are 26 species living in wooded areas from Tibet to Indonesia. [more]

Megalonychidae

Megalonychidae is a group of including the extinct Megalonyx and the living two toed sloths. Megalonychids first appeared in the early Oligocene, about 35 million years ago, in southern Argentina (Patagonia), and spread as far as the Antilles by the early Miocene. Megalonychids first reached North America by island-hopping, perhaps from the Antilles, about 9 million years ago. Some lineages of megalonychids increased in size as time progressed. The first species of these were small and may have been partly tree-dwelling, whereas the Pliocene (about 5 to 2 million years ago) species were already approximately half the size of the huge Late Pleistocene Megalonyx jeffersonii from the last ice age. Some West Indian island species were as small as a large cat; their dwarf condition typified both tropical adaptation and their restricted island environment. This small size also enabled them a degree of aboreality. [more]

Megalosauridae

[more]

Megapodiidae

The megapodes, also known as incubator birds or mound-builders, are stocky, medium-large chicken-like with small heads and large feet in the family Megapodiidae. Their name literally means large foot (Greek: mega = large, poda = foot), and is a reference to the heavy legs and feet typical of these terrestrial birds. All are browsers, all but the Malleefowl occupy wooded habitats, and most are brown or black colored. Megapodes are superprecocial, hatching from their eggs in the most mature condition of any birds. They hatch with open eyes, with bodily coordination and strength, with full wing feathers and downy body feathers, able to run, pursue prey, and, in some species, fly on the same day they hatch. [more]

Megatheriidae

[more]

Meiolaniidae

[more]

Melanocharitidae

The Melanocharitidae, the berrypeckers and longbills, is a small family restricted to the forests of New Guinea. The family was once placed inside the Flowerpecker family Dicaeidae, and the longbills were once considered to be honeyeaters (which they closely resemble). It comprises ten species in two genera, the Melanocharis berrypeckers and the Toxorhamphus. There is some confusion with the common names, as there are two other berrypecker species in the tiny family Paramythiidae, once considered to be close to the flowerpeckers as well; and several Old World warbler genera in Africa also known as longbills. The Spotted Berrypecker was once attributed its own genus Rhamphocharis. [more]

Melanorosauridae

[more]

Meliphagidae

The honeyeaters are a large and diverse family of small to medium sized birds most common in and New Guinea, but also found in New Zealand, the Pacific islands as far east as Samoa and Tonga, and the islands to the north and west of New Guinea known as Wallacea. Bali, on the other side of the Wallace Line, has a single species. [more]

Menuridae

A Lyrebird is either of two of ground-dwelling Australian birds, most notable for their superb ability to mimic natural and artificial sounds from their environment. Lyrebirds have unique plumes of neutral colored tailfeathers. [more]

Mephitidae

Skunks are best known for their ability to secrete a strong, foul-smelling odor. General appearance ranges from species to species, from black-and-white to brown or cream colored. Skunks belong to the family Mephitidae and to the order Carnivora. There are 10 species of skunks, which are divided into four genera: Mephitis (hooded and striped skunks, two species), Spilogale (spotted skunks, two species), Mydaus (stink badgers, two species), and Conepatus (hog-nosed skunks, four species). The two skunk species in the Mydaus genus inhabit Indonesia and the Philippines; all other skunks inhabit the Americas from Canada to central South America. [more]

Meropidae

The bee-eaters are a group of birds in the family Meropidae. Most species are found in Africa but others occur in southern Europe, Australia, and New Guinea. They are characterised by richly colored plumage, slender bodies, and usually elongated central tail feathers. All have long downturned bills and pointed wings, which give them a swallow-like appearance when seen from afar. There are 26 different species of bee-eaters. [more]

Merycoidodontidae

Sometimes called a "ruminating hog," although they are neither hogs, nor ruminants, the typical oreodont ("Mountain teeth") was a sheep-sized (though some genera grew to the size of cattle), herbivore with a short face, tusk-like canine teeth, heavy body, long tail, short feet, and four-toed hooves. [more]

Mesitornithidae

The mesites (Mesitornithidae) are a of birds of uncertain affinities. They are smallish, near flightless birds endemic to Madagascar. Generally brownish with paler undersides, they are of somewhat pheasant-like appearance and were initially placed with the Galliformes. Most commonly, they are placed in the Gruiformes (cranes, rails and allies), but this has been disputed in more recent times. They are the only family with more than two species in which every species is threatened; all three are listed as vulnerable and are expected to decline greatly in the next 20 years.[verification needed] [more]

Mesonychidae

[more]

Mesosauridae

[more]

Mesotheriidae

[more]

Metacheiromyidae

[more]

Metriorhynchidae

[more]

Miacidae

[more]

Microbiotheriidae

The is the only extant member of its family (Microbiotheriidae) and the only surviving member of an ancient order, the Microbiotheria. The oldest microbiothere currently recognised is Khasia cordillerensis, based on fossil teeth from Early Palaeocene deposits at Tiupampa, Bolivia. Numerous genera are known from various Palaeogene and Neogene fossil sites in South America. A number of possible microbiotheres, again represented by isolated teeth, have also been recovered from the Middle Eocene La Meseta Formation of Seymour Island, Western Antarctica. Finally, several undescribed microbiotheres have been reported from the Early Eocene Tingamarra Local Fauna in Northeastern Australia; if this is indeed the case, then these Australian fossils have important implications for our understanding of marsupial evolution and biogeography. [more]

Micromomyidae

[more]

Micropternodontidae

[more]

Microsyopidae

[more]

Mimotonidae

[more]

Mioclaenidae

[more]

Miralinidae

[more]

Mixodectidae

[more]

Moeritheriidae

[more]

Molossidae

Molossidae, or Free-tailed bats, are a family of bats within the order. They are generally quite robust, and consist of many strong flying forms with relatively long and narrow wings. Another common name for some members of this group, and indeed a few species from other families, is Mastiff Bat. The Western mastiff bat, Eumops perotis, a large species from the southwestern United States and Mexico with wings over half a metre across, is perhaps one of the best known with this name. They are widespread, being found on every continent except Antarctica. [more]

Momotidae

The motmots or Momotidae are a of birds in the near passerine order Coraciiformes, which also includes the kingfishers, bee-eaters and rollers. All extant motmots are restricted to woodland or forest in the Neotropics, and the largest diversity is in Middle America. They have a colorful plumage and a relatively heavy bill. All except the Tody Motmot have relatively long tails that in some species has a distinctive racket-like tip. [more]

Monodontidae

The family Monodontidae comprises two unusual whale species, the Narwhal, in which the male has a long tusk, and the white Beluga. They are native to coastal regions and pack ice around the Arctic Sea, and the far north of the Atlantic and Pacific Oceans. [more]

Morganucodontidae

[more]

Mormoopidae

The family Mormoopidae contains known generally as moustache bats, ghost-faced bats, and naked-backed bats. They are found in Central and South America, from Southern Mexico to Southeastern Brazil. [more]

Mosasauridae

Mosasaurs (from Mosa meaning the 'Meuse river' in the Netherlands, and Greek sauros meaning 'lizard') were serpentine marine reptiles. The first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764. These ferocious marine predators are now considered to be the closest relatives of snakes, due to cladistic analysis of symptomatic similarities in jaw and skull anatomies. Mosasaurs were not dinosaurs but lepidosaurs, reptiles with overlapping scales. These predators evolved from semi-aquatic squamates known as the aigialosaurs, close relatives of modern-day monitor lizards, in the Early Cretaceous Period. During the last 20 million years of the Cretaceous Period (Turonian-Maastrichtian), with the extinction of the ichthyosaurs and pliosaurs, mosasaurs became the dominant marine predators. [more]

Moschidae

Musk deer are of the genus Moschus, the only genus of family Moschidae. They are more primitive than the cervids, or true deer, in not having antlers or facial glands, in having only a single pair of teats, and in possessing a gall bladder, a caudal gland, a pair of tusk-like teeth and—of particular economic importance to humans—a musk gland. Moschids live mainly in forested and alpine scrub habitats in the mountains of southern Asia. [more]

Muridae

Muridae is the largest family of . It contains over 600 species found naturally throughout Eurasia, Africa, and Australia. They have been introduced worldwide. The group includes true mice and rats, gerbils, and relatives. [more]

Muscicapidae

The Old World flycatcher family Muscicapidae is a large family of small birds restricted to the Old World. These are mainly small arboreal insectivores, many of which, as the name implies, take their prey on the wing. [more]

Musophagidae

The turacos make up the family Musophagidae (literally "banana-eaters"), which includes plantain-eaters and go-away-birds. In southern Africa both turacos and go-away-birds are commonly known as louries. They are semi-zygodactylous - the fourth (outer) toe can be switched back and forth. The second and third toes, which always point forward, are conjoined in some species. Musophagids often have prominent crests and long tails; the turacos are noted for peculiar and quite unique pigments giving them their bright green and red feathers. [more]

Mustelidae

Mustelidae or Mustelids (from Latin mustela, ), commonly referred to as the weasel family, is a family of carnivorous mammals. The Mustelidae is a diverse family and the largest in the order Carnivora, at least partly because it has in the past been a catch-all category for many early or poorly differentiated taxa. [more]

Mylagaulidae

[more]

Mylodontidae

Mylodontidae is a family of extinct mammals within the order of and suborder Folivora. This family of ground sloths is related to the other families of extinct ground sloths, being the Megatheriidae, the Mylodontidae, the Nothrotheriidae, the Orophodontidae and the Scelidotheriidae. The only extant families of the suborder Folivora are the Bradypodidae and the Megalonychidae. [more]

Myrmecobiidae

Numbat, the species Myrmecobius fasciatus, is a found in Western Australia. Its diet consists almost exclusively of termites. Once widespread across southern Australia, the range is now restricted to several small colonies and it is listed as an endangered species. The Numbat is an emblem of Western Australia and protected by conservation programs. [more]

Myrmecophagidae

Myrmecophagidae is a family of , the name being derived from the Ancient Greek words for 'ant' and 'eat' (Myrmeco- and phagos). Myrmecophagids are native to Central and South America, from southern Mexico to northern Argentina. There are 2 genera and 3 species in the family, consisting of the Giant Anteater, and the Tamanduas. The fossil Eurotamandua from the Messel Pit in Germany may be an early anteater, but its status is currently debated. [more]

Mystacinidae

Mystacinidae is a family of unusual , the New Zealand short-tailed bats. There is one genus, Mystacina, with two species, one of which is believed to have become extinct in the 1960s. They are medium-sized bats, about 6 cm in length, with grey, velvety fur. [more]

Myzopodidae

Myzopoda is the only genus in family Myzopodidae, a family of . [more]

Nandiniidae

The African Palm Civet (Nandinia binotata), also known as the Two-spotted Palm Civet, is a small , with short legs, small ears, a body resembling a cat, and a long lithe tail as long as its body. Adults usually weigh 1.70 to 2.10 kg (3.7 to 4.6 lb). It is native to the forests of eastern Africa, where it usually inhabits trees. Its diet is omnivorous, and includes rodents, insects, eggs, carrion, fruit, birds and fruit bats. The animal is generally solitary and nocturnal. [more]

Natalidae

The Natalidae, or funnel-eared bats are found from Mexico to Brazil and the Caribbean islands. The family comprises only one a single genus, Natalus. They are slender bats with unusually long tails and, as their name suggests, funnel-shaped ears. They are small, at only 3.5 to 5.5 cm in length, with brown, grey, or reddish fur. Like many other bats, they are insectivorous, and roost in caves. [more]

Necrosauridae

[more]

Nectariniidae

The sunbirds and spiderhunters are a , Nectariniidae, of very small passerine birds. There are 132 species in 15 genera. The family is distributed throughout Africa, southern Asia and just reaches northern Australia. Most sunbirds feed largely on nectar, although they will also take insects, especially when feeding young. Fruit is also part of the diet of some species. Their flight is fast and direct on their short wings. [more]

Neomorphidae

Neomorphidae is a proposed family of , separating the ground cuckoos (including roadrunners) from the rest of the cuckoo family. It is traditionally nested within the family Cuculidae as the subfamily Neomorphinae. [more]

Nesophontidae

The members of the genus Nesophontes, sometimes called West Indies shrews, were members of the family of mammals Nesophontidae in the order Soricomorpha. This is the only genus described for this family. These animals were endemic to Cuba, Hispaniola (Dominican Republic and Haiti), Puerto Rico and the Cayman Islands. Although exact estimates are unavailable, these animals are widely believed to have survived the Pleistocene extinction since remains have been found among those of Rattus and Mus species. Some authorities estimate extinction coinciding with the arrivals of rats (Rattus spp.) aboard Spanish vessels in the early 16th century (1500). Others, such as Morgan and Woods, claim that some species survived until the early 20th century. [more]

Nimravidae

The Nimravidae, sometimes known as false sabre-tooths, are an family of mammalian carnivores living from the Eocene through the Miocene epochs (42—7.2 mya), existing for approximately . [more]

Noctilionidae

The Noctilionidae family of , commonly known as bulldog bats or fisherman bats, are represented by two species, the Greater Bulldog Bat and the Lesser Bulldog Bat. They are found near water, from Mexico to Argentina. The Naked Bulldog Bat (Cheiromeles torquatus) does not belong to this family, but to the family Molossidae, the free-tailed bats. [more]

Nodosauridae

Nodosauridae is a family of dinosaurs, from the Cretaceous Period of what are now North America, Asia, Australia, Antarctica and Europe. [more]

Nothosauridae

[more]

Notohippidae

[more]

Notoryctidae

The two species of marsupial moles are rare and poorly understood burrowing of the deserts of Western Australia. [more]

Notostylopidae

Notostylopidae is an family comprising five genera of notoungulate mammals known from the early Eocene to early Oligocene of South America [more]

Notosuchidae

[more]

Numididae

The guinea fowl (sometimes called guinea hen) are a family of in the Galliformes order, although some authorities (for example the American Ornithologists' Union) include the guinea fowl as a subfamily, Numidinae, of the family Phasianidae. The guinea fowl are native to Africa, but the Helmeted Guinea fowl has been domesticated and both feral and wild-type birds have been introduced elsewhere. [more]

Nycteridae

Nycteridae is the family of slit-faced or hollow-faced bats. They are grouped in a single , Nycteris. The bats are found in East Malaysia, Indonesia and many parts of Africa. [more]

Nyctibiidae

The potoos are a , Nyctibiidae of near passerine birds related to the nightjars and frogmouths. They are sometimes called Poor-me-ones, after their haunting calls. There are seven species in one genus, Nyctibius, in tropical Central and South America. [more]

Nyctitheriidae

[more]

Ochotonidae

Pikas, cousins of rabbits, are small -like animals, with short limbs, rounded ears, and short tails. The name pika (archaically spelled pica) is used for any member of the Ochotonidae, a family within the order of lagomorphs, which also includes the Leporidae (rabbits and hares). One genus, Ochotona, is recognised within the family, and it includes 30 species. Pikas are also called rock rabbits or coneys. It is also known as the "whistling hare" due to its high-pitched alarm call when diving into its burrow. The name "pika" appears to be derived from the Tungus "piika", or perhaps from the Russian "pikat", to squeak. In English the pronunciation of the name is usually anglicised from /pika/(peeka) to /'pa?·ka/, due to the spelling. [more]

Octodontidae

The Octodontidae are a rodents, restricted to south-western South America. Thirteen species of octodontid are recognised, arranged in nine genera. The best known species is the Degu, Octodon degus. [more]

Odobenocetopsidae

[more]

Odontophoridae

The New World quails are small birds only distantly related to the of the Old World, but named for their similar appearance and habits. The American species are in their own family Odontophoridae, whereas the Old World birds are in the pheasant family Phasianidae. The family ranges from Canada through to southern Brazil, and one species, the California Quail, has been successfully introduced to New Zealand. A variety of habitats are used by the family from tropical rainforest to deserts, although few species are capable of surviving at very low temperatures. There are 32 species in nine genera. [more]

Oldfieldthomasiidae

[more]

Omomyidae

Omomyids (members of the Omomyidae) are a diverse group of extinct primates that radiated during the Eocene epoch (34 to 59 mya) between about 55 and 34 million years ago (mya). Fossils of omomyids are found in North America, Europe, Asia, and possibly Africa. Omomyids are one of two groups of Eocene primates with a geographic distribution spanning holarctic continents, the other being the adapids (family Adapidae). Early representatives of the Omomyidae and Adapidae appear suddenly at the beginning of the Eocene (59 mya) in North America, Europe, and Asia, and are the earliest known crown primates. [more]

Omphalosauridae

[more]

Ophiacodontidae

[more]

Opisthocomidae

The Hoatzin (Opisthocomus hoazin), also known as the Hoactzin, Stinkbird, or Canje "Pheasant", is an unusual species of bird found in swamps, riverine forest and mangrove of the Amazon and the Orinoco delta in South America. It is the only member of the genus Opisthocomus (Ancient Greek: wearing long hair behind, referring to its large crest), which in turn is the only extant genus in the family Opisthocomidae. The taxonomic position of this family has been greatly debated, and is still far from clear. It is a roughly pheasant-sized bird some 65 cm (25 in), with a long neck and small head. It is brown in color, with paler underparts and has an unfeathered blue face with maroon eyes, and its head is topped by a spiky, rufous crest. The chicks are unusual in that two of their wing digits possess claws. The Hoatzin is herbivorous, it eats leaves and fruit, and has an unusual digestive system with an enlarged crop which functions as a rumen. [more]

Opluridae

The Opluridae, or Madagascan Iguanas, are a family of moderately sized lizards native to . The family includes species that live amongst rocks, some that live in trees, and one that inhabits sand dunes. All of the species lay eggs, and have teeth that resemble those of the true iguanas. [more]

Ornithocheiridae

[more]

Ornithomimidae

[more]

Ornithorhynchidae

Ornithorhynchidae is one of the two extant families in the order , and contains the Platypus and its extinct relatives. The other family is the Tachyglossidae, or echidnas. Within Ornithorhynchidae are two genera, Obdurodon and Ornithorhynchus: [more]

Ornithosuchidae

[more]

Oromerycidae

[more]

Orthonychidae

The Orthonychidae is a of birds with a single genus, Orthonyx, which comprises three species of passerine birds endemic to Australia and New Guinea, the Logrunners and the Chowchilla. Some authorities consider the Australian family Cinclosomatidae to be part of the Orthonychidae. The three species use their stiffened tails to brace themselves when feeding. [more]

Orycteropodidae

The Aardvark (Orycteropus afer) (: from Africa) is a medium-sized, burrowing, nocturnal mammal native to Africa. It is sometimes called "antbear", "anteater", "Cape anteater" (after the Cape of Good Hope), "earth hog" or "earth pig". The name comes from the Afrikaans/Dutch for "earth pig" (aarde earth, varken pig), because early settlers from Europe thought it resembled a domesticated pig. However, the aardvark is not closely related to the pig; rather, it is the sole recent representative of the obscure mammalian order Tubulidentata, in which it is usually considered to form a single variable species of the genus Orycteropus, coextensive with the family Orycteropodidae. The aardvark is not closely related to the South American anteater, despite sharing some characteristics and a superficial resemblance. The closest living relatives of the aardvark are the elephant shrews, along with the sirenians, hyraxes, tenrecs, and elephants. [more]

Otariidae

The eared seals or otariids are in the family Otariidae, one of three groupings of Pinnipeds. They comprise 16 species in seven genera commonly known either as sea lions or fur seals, distinct from true seals (phocids) and the Walrus (odobenids). Otariids are adapted to a semi-aquatic lifestyle, feeding and migrating in the water but breeding and resting on land or ice. They reside in subpolar, temperate, and equatorial waters throughout the Pacific and Southern oceans and the southern Indian and Atlantic oceans. They are conspicuously absent in the north Atlantic. [more]

Otididae

Bustards, including floricans and korhaans, are large terrestrial mainly associated with dry open country and steppes in the Old World. They make up the family Otididae (formerly known as Otidae). They were renowned by the ancient Arabs for being unusually stupid. [more]

Oviraptoridae

[more]

Oxyaenidae

[more]

Oxyclaenidae

[more]

Pachycephalosauridae

[more]

Pachyophiidae

[more]

Pachypleurosauridae

[more]

Palaechthonidae

[more]

Palaelodidae

[more]

Palaeomastodontidae

[more]

Palaeomerycidae

[more]

Palaeoryctidae

[more]

Palaeotheriidae

Palaeotheres are an extinct group of mammals related to tapirs and rhinoceros and probably ancestral to horses. They ranged across the Northern Hemisphere 60 to 45 million years ago. Their size ranged from 20 to 75 cm at the shoulder. They ate soft leaves, plant shoot, berries, and leaf matter picked up from the forest floor. They lived in dense forests. [more]

Palorchestidae

[more]

Pampatheriidae

[more]

Pantolambdidae

[more]

Pantolestidae

[more]

Pappotheriidae

[more]

Paralligatoridae

[more]

Paramacellodidae

[more]

Paramythiidae

The painted berrypeckers, Paramythiidae, are a very small family restricted to the mountain forests of New Guinea. The family comprises two species in two genera: the Tit Berrypecker (Oreocharis arfaki) and the Crested Berrypecker (Paramythia montium). These are colorful medium-sized birds which feed on fruit and some insects. These species were formerly included in the Dicaeidae, but DNA-DNA hybridization studies showed these species were related to each other but distinct from the flowerpeckers. [more]

Parapithecidae

[more]

Parasaniwidae

[more]

Pardalotidae

Pardalotes are a , Pardalotidae, of very small, brightly colored birds native to Australia, with short tails, strong legs, and stubby blunt beaks. This family is composed of four species in one genus, Pardalotus, and several subspecies. The name derives from a Greek word meaning "spotted". The family once contained several other species now split into the family Acanthizidae. [more]

Pareiasauridae

[more]

Paridae

The tits, chickadees, and titmice comprise Paridae, a large family of small birds which occur in the northern hemisphere and Africa. Most were formerly classified in the genus Parus. [more]

Paromomyidae

[more]

Paroxyclaenidae

[more]

Passeridae

True sparrows, the sparrows in the family Passeridae, are small passerine birds. As eight or more species nest in or near buildings, and the House Sparrow and Eurasian Tree Sparrow in particular inhabit cities in large numbers, sparrows may be the most familiar of all wild birds. [more]

Patriocetidae

[more]

Pedetidae

The springhare (Pedetes capensis), or springhaas, is not actually a , but a member of the order Rodentia; it is the only species in its family Pedetidae and in the genus Pedetes. Synonyms are P. caffer or P. cafer. [more]

Pediomyidae

[more]

Pedionomidae

The Plains Wanderer, Pedionomus torquatus, is a unique and is put in a family of its own. It is endemic to Australia. [more]

Pelecanidae

A pelican is a large water with a distinctive pouch under the beak, belonging to the bird family Pelecanidae. [more]

Pelomedusidae

Pelomedusidae is a of freshwater turtles, native to eastern and southern Africa. They range in size from 12 centimetres (4.7 in) to 45 centimetres (18 in) in shell length, and are generally roundish in shape. They are unable to fully withdraw their heads into their shells, instead drawing it to the side and folding it beneath the upper edge of the shell, and hence are called African side-necked turtles. [more]

Peramelidae

Peramelidae is the family of that contains all of the extant bandicoots. One known extinct species of bandicoot, the Pig-footed Bandicoot, was so different than the other species that it was recently moved into its own family. There are four described fossil Peramelids. They are found throughout Australia and New Guinea, with at least some species living in every available habitat, from rain forest to desert. [more]

Peramuridae

[more]

Periptychidae

[more]

Peroryctidae

The New Guinean long-nosed bandicoots ( Peroryctes) are members of the Peramelemorphia order. They are small to medium sized marsupial omnivores native to New Guinea. [more]

Petauridae

The Petauridae includes 11 medium-sized possum species: four striped possums, the six species wrist-winged gliders in genus Petaurus, and Leadbeater's Possum which has only vestigal gliding membranes. Most of the wrist-winged gliders are native to Australia, most of the striped possums (genus Dactylopsila) to New Guinea, but some members of each are found on both sides of Torres Strait. [more]

Petroicidae

The family Petroicidae includes roughly 45 species in about 15 genera. All are endemic to Australasia or nearby areas. For want of a more accurate common name, the family is often described as the Australasian robins. The family occurs in New Guinea, Australia and numerous Pacific Islands as far east as Samoa. Within the family the species are known not only as robins but the flycatchers, and scrub-robins. They are however unrelated to Old World family Muscicapidae (to which other species with such names belong), or the monarch flycatchers (Monarchidae). [more]

Petromuridae

The Dassie Rat, Petromus typicus, is an rodent found among rocky outcroppings. It is the only living member of its genus, Petromus, and family, Petromuridae. The name "dassie" means "hyrax" in Afrikaans, and the two animals are found in similar habitats. Petromus means "rock mouse" and dassie rats are one of many rodents that are sometimes called rock rats. The family and genus names are sometimes misspelled as Petromyidae and Petromys. [more]

Phaethontidae

Tropicbirds are a , Phaethontidae, of tropical pelagic seabirds now classified in their own order Phaethontiformes. Their relationship to other living birds is unclear, and they appear to have no close relatives. There are three species in one genus Phaethon. They have predominately white plumage with elongated tail feathers and small feeble legs and feet. [more]

Phalacrocoracidae

The family Phalacrocoracidae is represented by some 40 species of cormorants and shags. Several different classifications of the family have been proposed recently, and the number of genera is disputed. [more]

Phalangeridae

Phalangeridae is a family of marsupials native to Australia and New Guinea, including the cuscuses, brushtail possums, and their close relatives. Considered a type of possum, most species are arboreal, and they inhabit a wide range of forest habitats from alpine woodland to eucalypt forest and tropical jungle. [more]

Phascolarctidae

Phascolarctidae is a family of of the order Diprotodontia, consisting of only one extant species, the Koala, six well known fossil species, with another 5 less well known fossil species, and 2 fossil species whose taxonomy is debatable but is put in this group. The closest relatives of the Phascolarctidae are the wombats, which comprise the family Vombatidae. [more]

Phasianidae

The Phasianidae is a of birds which consists of the pheasants and partridges, and including the junglefowl (including chicken), Old World quail, francolins, monals and peafowl. The family is a large one, containing 38 genera and around 138 species. The family is occasionally broken up into two subfamilies, the Phasianinae, which holds 49 species of pheasant, and the Perdicinae, which holds the 106 remaining species. Sometimes additional families and birds are treated as being in this family as well; the American Ornithologists' Union includes Tetraonidae (the grouse), Numididae (guineafowls), and Meleagrididae (turkeys) in Phasianidae as subfamilies. [more]

Phenacodontidae

[more]

Phenacolophidae

[more]

Philepittidae

The asities, are a , the Philepittidae, of small suboscine passerine birds. The family consists of four species in two genera endemic to Madagascar. They were thought to have been related to the pittas, hence the scientific name of the family, but a 1993 study suggested that they are actually just a subfamily of broadbills. The morphology of the syrinx is very similar to the Grauer's Broadbill of Africa. Here they are considered traditionally as a separate family. Some authors have placed the Broad-billed Sapayoa of South America in the family, although it is now mostly considered a broadbill. The Neodrepanis species are known as sunbird-asities and were formerly known as false sunbirds. [more]

Phocidae

The true seals or earless seals are one of the three main groups of within the seal suborder, Pinnipedia. All true seals are members of the family Phocidae . They are sometimes called crawling seals to distinguish them from the fur seals and sea lions of the family Otariidae. Seals live in the oceans of both hemispheres and are mostly confined to polar, sub-polar, and temperate climates, with the exception of the more tropical monk seals. [more]

Phocoenidae

Porpoises are cetaceans of the family Phocoenidae; they are related to whales and dolphins. They are distinct from dolphins, although the word "porpoise" has been used to refer to any small dolphin, especially by sailors and fishermen. The most obvious visible difference between the two groups is that porpoises have flattened, spade-shaped teeth distinct from the conical teeth of dolphins, and shorter beaks. [more]

Phoenicopteridae

Flamingos or flamingoes ( pronunciation (help·info)) are gregarious wading birds in the genus Phoenicopterus and family Phoenicopteridae. They are found in both the Western Hemisphere and in the Eastern Hemisphere, but are more numerous in the latter. There are four species in the Americas and two species in the Old World. Two species, the Andean and the James's Flamingo, are often placed in the genus Phoenicoparrus instead of Phoenicopterus. [more]

Phoeniculidae

The Woodhoopoes and scimitarbills are a small family, Phoeniculidae, of near passerine birds. They live south of the Sahara Desert and are not migratory. While the family is now restricted to sub-Saharan Africa, fossil evidence shows that the family once had a larger distribution. Fossils attributed to this family have been found in Miocene rocks in Germany. [more]

Phrynosomatidae

Phrynosomatidae is a diverse family of , found from Panama to the extreme south of Canada. Many members of the group are adapted to life in hot, sandy deserts, although the spiny lizards prefer rocky deserts or even relatively moist forest edges, and the short-horned lizard lives in prairie or sagebrush environments. The group includes both egg-laying and viviparous species, with the latter being more common in species living at high elevation. [more]

Phyllostomidae

The New World leaf-nosed bats (Phyllostomidae) are found throughout Central and South America, from to northern Argentina. They are ecologically the most varied and diverse family within the order Chiroptera. Most species are insectivorous, but the phyllostomid bats include within their number true predatory species as well as frugivores (subfamily Stenodermatinae and Carolliinae). For example, the False Vampire, Vampyrum spectrum, the largest bat in the Americas, eats vertebrate prey including small dove-sized birds. Members of this family have evolved to utilize food groups such as fruit, nectar, pollen, insects, frogs, other bats and small vertebrates, and, in the case of the vampire bats, even blood. [more]

Physeteridae

The sperm whale family, or sperm whales, is a common name for the Physeteridae or superfamily Physeteroidea. The three existing species of whale are the Sperm Whale, in the genus Physeter, and the Pygmy Sperm Whale and Dwarf Sperm Whale, in the genus Kogia. In the past these genera have sometimes been united in the single family, Physeteridae, with the two Kogia species in a subfamily (Kogiinae), however recent practice is to allocate the genus Kogia to its own family, Kogiidae, leaving Physeteridae as a monotypic (single extant species) family, although additional fossil representatives of both families are known (see "Evolution"). The name Sperm Whale comes from sailors of whaling boats who thought that the spermaceti on the whales head was actual sperm from the reproductive system. [more]

Phytosauridae

[more]

Picathartidae

The picathartes, rockfowl or bald crows are a small genus of two bird species within the family Picathartidae found in the rain-forests of tropical west and central Africa. They have unfeathered heads, and feed on insects and invertebrates picked from damp rocky areas. Both species are totally non-migratory, being dependent on a specialised rocky jungle habitat. [more]

Picidae

The woodpeckers, piculets and wrynecks are a , Picidae, of near-passerine birds. Members of this family are found worldwide, except for Australia and New Zealand, Madagascar, and the extreme polar regions. Most species live in forests or woodland habitats, although a few species are known to live in treeless areas such as rocky hillsides and deserts. [more]

Picopsidae

[more]

Picrodontidae

[more]

Pilkipildridae

[more]

Pittidae

Pittas are a , Pittidae, of passerine birds mainly found in tropical Asia and Australasia, although a couple of species live in Africa. Pittas are all similar in general structure and habits, and are placed in a single genus, Pitta. The name is derived from the word pitta in the Telugu language of Andhra Pradesh in India and is a generic local name used for all small birds. [more]

Placodontidae

[more]

Plagiaulacidae

[more]

Plagiomenidae

[more]

Platanistidae

The Ganges River Dolphin (Platanista gangetica gangetica) and Indus River Dolphin (Platanista gangetica minor) are two sub-species of freshwater or found in Bangladesh, India, Nepal and Pakistan. The Ganges River Dolphin is primarily found in the Ganges and Brahmaputra Rivers and their tributaries in India, Bangladesh and Nepal, while the Indus River Dolphin is found in the Indus river in Pakistan and the Beas and Sutlej rivers in India. From the 1970s until 1998, they were regarded as separate species; however, in 1998, their classification was changed from two separate species to subspecies of a single species (see taxonomy below). [more]

Plateosauridae

[more]

Plesiadapidae

[more]

Plesiosoricidae

[more]

Pleurosauridae

[more]

Pleurosternidae

[more]

Pliohyracidae

[more]

Pliopithecidae

[more]

Pliosauridae

[more]

Plotopteridae

[more]

Pluvianellidae

The Magellanic Plover, Pluvianellus socialis, is a rare and unique found only in southernmost South America. It was long placed in with the other plovers in the family Charadriidae, however behavioural evidence suggested they were distinct, and molecular studies confirmed this, suggesting that they are actually more closely related to the sheathbills, an uniquely Antarctic family. As such it is now placed in its own family, Pluvianellidae. This species is not a long distance migratant, although some birds move further north in southern Argentina in winter. The species breeds inland and then moves to the coast during the winter, particularly to estuaries. [more]

Podargidae

The frogmouths are a group of birds related to the nightjars. They are found from India across southern Asia to Australia. [more]

Podicipedidae

A grebe is a member of the Podicipediformes , a widely distributed order of freshwater diving birds, some of which visit the sea when migrating and in winter. This order contains only a single family, the Podicipedidae, containing 22 species in 6 extant genera. [more]

Podocnemididae

[more]

Polychrotidae

Polychrotidae is a family of commonly known as Anoles . NCBI places the anole in subfamily Polychrotinae of the family Iguanidae. Four genera are common: Anolis, Norops, Phenacosaurus and Polychrus. [more]

Polycotylidae

[more]

Polydolopidae

[more]

Pomatostomidae

The Pomatostomidae (Australo-Papuan or Australasian babblers, also known as pseudo-babblers) are small to medium-sized birds endemic to . For many years, the Australo-Papuan babblers were classified, rather uncertainly, with the Old World babblers (Timaliidae), on the grounds of similar appearance and habits. More recent research, however, indicates that they are too basal to belong the Passerida - let alone the Sylvioidea where the Old World babblers are placed - and they are now classed as a separate family close to the Orthonychidae (logrunners). [more]

Pontoporiidae

The La Plata Dolphin or Franciscana (Pontoporia blainvillei) is found in coastal Atlantic waters of southeastern . Taxonomically it is a member of the river dolphin group and the only one that actually lives in the ocean and saltwater estuaries, rather than inhabiting exclusively freshwater systems. [more]

Poposauridae

[more]

Potamotelsidae

[more]

Prestosuchidae

[more]

Procaviidae

A hyrax (from Greek "shrewmouse") is any of four of fairly small, thickset, herbivorous mammals in the order Hyracoidea. They live in Africa and the Middle East. [more]

Procellariidae

The Procellariidae is a group of seabirds that comprises the fulmarine petrels, the gadfly petrels, the prions, and the shearwaters. This family is part of the bird order Procellariiformes (or tubenoses), which also includes the albatrosses, the storm-petrels, and the diving petrels. [more]

Procolophonidae

[more]

Procyonidae

Procyonidae is a New World of the order Carnivora. It includes the raccoons, coatis, kinkajous, olingos, ringtails and cacomistles. Procyonids inhabit a wide range of environments, and are generally omnivorous. [more]

Proganochelyidae

[more]

Prorastomidae

[more]

Proscalopidae

[more]

Proterotheriidae

[more]

Protoavidae

[more]

Protoceratidae

[more]

Protoceratopsidae

[more]

Protocetidae

[more]

Protoptychidae

[more]

Protostegidae

[more]

Protosuchidae

[more]

Pseudictopidae

[more]

Psittacidae

The true parrots are about 330 species of bird belonging to the Psittacidae , one of the two "traditional" families in the biological order Psittaciformes (parrots). The other family is the Cacatuidae (cockatoos) which are also parrots, but not classified as true parrots. True parrots are more widespread than cockatoos, with species in the Americas, Africa, Asia, Australia and eastwards across the Pacific Ocean as far as Polynesia. [more]

Psittacosauridae

Psophiidae

The trumpeters are a small family of restricted to the forests of the Amazon and Orinoco basins in South America. They are named for the trumpeting or cackling threat call of the males. The three species resemble chickens in size; they measure 45 to 52 centimeters (18 to 20 inches) long and weigh 1 to 1.5 kilograms (2.2 to 3.3 pounds). They are dumpy birds with long necks and legs and curved bills and a hunched posture. Their heads are small, but their eyes are relatively large, making them look "good-natured". The plumage is soft, resembling fur or velvet on the head and neck. It is mostly black, with purple, green, or bronze iridescence, particularly on the wing coverts and the lower neck. The secondary and tertial flight feathers are white, gray, or greenish to black, and hairlike, falling over the lower back, which is the same color. These colors give the three species their names. [more]

Pteranodontidae

[more]

Pterodactylidae

[more]

Pteropodidae

Megabats is the term used informally to refer to bats of the family Pteropodidae (as opposed to ). They are also referred to as fruit bats, old world fruit bats, or flying foxes. According to the most commonly used classification, megabats constitute a single suborder Megachiroptera, within the order Chiroptera (bats). [more]

Ptilodontidae

[more]

Ptilonorhynchidae

This article is about the family of birds called bowerbirds. For the band, see . [more]

Purgatoriidae

[more]

Pycnonotidae

Bulbuls (Pycnonotidae) are a of medium-sized passerine songbirds. Many forest species are known as greenbuls. The family is distributed across most of Africa and into the Middle East, tropical Asia to Indonesia, and north as far as Japan. A few insular species occur on the tropical islands of the Indian Ocean There are about 130 species in around 24 genera. While some species are found in most habitats, overall African species are predominately found in rainforest whilst rainforest species are rare in Asia, instead preferring more open areas. The only Bulbul which occurs in Europe was spotted in the Cyclades and bears a yellow patch, being otherwise of a snuffy brown ; and this is possibly the bird which has got mixed up with the nightingale in Eastern poetry, as it occurs in Israel, and is there called "bulbul" in Hebrew by the Israelis as well as in Arabic and Persian language. [more]

Pygopodidae

Pygopodidae (or fogs) is a family of snakes with legs related to the . They have unusually long, slender, bodies, giving them a strong resemblance to snakes. Like both snakes and most geckos, they have no eyelids, but unlike snakes, they have external ear-holes and flat, non-forked tongues. They are native to Australia and New Guinea. [more]

Pyrotheriidae

[more]

Rallidae

The rails, or Rallidae, are a large family of small to medium-sized birds. The family exhibits considerable diversity and the family also includes the crakes, coots, and gallinules. Many species are associated with wetlands, although the family is found in every terrestrial habitat except dry deserts, polar regions and alpine areas above the snow line. [more]

Ramphastidae

Toucans are a family, Ramphastidae, of birds from the neotropics (i.e. Southern Mexico, Central, South American, and Caribbean region). The family is most closely related to the American barbets. They are brightly marked and have large, colorful bills. The family includes five genera and about forty different species. The name of this bird group is derived from Tupi tucana, via French. [more]

Raoellidae

[more]

Raphidae

The Raphinae are a of extinct flightless birds colloquially called didines or didine birds. They inhabited the Mascarene Islands of Mauritius and Rodrigues, but became extinct through hunting by humans and predation by introduced non-native mammals following human colonisation in the 1600s. [more]

Rauisuchidae

[more]

Regulidae

The kinglets or crests are a small group of birds sometimes included in the , but are frequently given family status because they also resemble the titmice. The scientific name Regulidae is derived from the Latin word regulus for "petty king" or prince, and comes from the colored crowns of adult birds. This family has representatives in North America and Eurasia. There are seven species in this family; one, the Madeira Firecrest, Regulus madeirensis, was only recently split from Firecrest as a separate species. One species, the Ruby-crowned Kinglet, differs sufficiently in its voice and plumage to occasionally be afforded its own genus, Corthylio. [more]

Reithroparamyidae

[more]

Remingtonocetidae

[more]

Rhabdosteidae

[more]

Rhamphorhynchidae

[more]

Rheidae

The rheas are species of (flightless birds, with unkeeled sterna) in the genus Rhea, native to South America. There are two existing species: the Greater or American Rhea and the Lesser or Darwin's Rhea. The genus name was given in 1752 by Paul Mohring and adopted as the English common name. Mohring's reason for choosing this name, from the Rhea of classical mythology, is not known. [more]

Rhinocerotidae

Rhinoceros , often colloquially abbreviated rhino, is a name used to group five extant species of in the family Rhinocerotidae. Two of these species are native to Africa and three to southern Asia. Three of the five species—the Javan, Sumatran and Black Rhinoceros—are critically endangered. The Indian is endangered, with fewer than 2,700 individuals remaining in the wild. The White is registered as Vulnerable, with approximately 17,500 remaining in the wild, as reported by the Intenational Rhino Foundation. The Rhinoceros Beetle is named as such due to its horns, which simulate rhino's horns. [more]

Rhinocryptidae

The tapaculos are a group of small passeriform birds with numerous species, found mainly in South America and with the highest diversity in the Andean regions. Three species, the Choco, the Pale-throated and the Silvery-fronted Tapaculo, are found in southern Central America. [more]

Rhinolophidae

Horseshoe bats (the Rhinolophidae family) are a large family of bats including approximately 130 species grouped into ten . They either belong to the suborder Microchiroptera (microbats) or the Yinpterochiroptera. [more]

Rhinopomastidae

Scimitarbills (also spelt Scimitar-bills) are three species of bird belonging to the genus Rhinopomastus. They are often classified in the woodhoopoe family Phoeniculidae; however, genetic studies show that they diverged from the true woodhoopoes about 10 million years ago and so they are sometimes placed in a family of their own, the Rhinopomastidae. [more]

Rhinopomatidae

Mouse-tailed bats are a group of bats of the family Rhinopomatidae with only three species, all contained in the single genus Rhinopoma. They are found in the Old World, from North Africa to Thailand and Sumatra, in arid and semi-arid regions, roosting in caves, houses and even the Egyptian pyramids. They are relatively small, with a body length of just 5 to 6 centimetres. [more]

Rhynchosauridae

[more]

Rhynochetidae

The Kagu (: ), Rhynochetos jubatus, is a long-legged blue-greyish bird endemic to the dense mountain forests of New Caledonia. It is the only surviving member of the family Rhynochetidae, although a second, larger species of the genus Rhynochetos, the Lowland Kagu Rhynochetos orarius, has been described from Holocene subfossil remains. It is almost flightless, and builds a ground nest of sticks, laying a single egg. It has proved vulnerable to introduced predators, and is threatened with extinction. The remote habitat and rarity of this species mean that little is known of its habits. [more]

Rostratulidae

Painted snipes are three distinctive species in the family Rostratulidae. The family is composed to two genera, Rostratula and Nycticryphes. The Australian Painted Snipe is often treated as a subspecies of the Greater Painted Snipe. While they superficially resemble true snipes, they are considered to be more closely related to the jacanas. [more]

Rotodactylidae

[more]

Saltoposuchidae

[more]

Scaloposauridae

[more]

Scelidosauridae

[more]

Scincidae

A Family in the Kingdom Animalia. [more]

Sciuravidae

[more]

Sciuridae

The sciurids or are a large family of rodents. The word Sciuridae means "shade-tail," and refers to the bushy appendage possessed by many of its members. It includes tree squirrels, ground squirrels, chipmunks, the marmots (which include woodchucks), and the true flying squirrels. The African scaly-tailed flying squirrels, which belong to the family Anomaluridae, are not sciurids. Sciurids are found in all continents except Australia and Antarctica. [more]

Scleromochlidae

[more]

Scolopacidae

The Scolopacidae are a large family of , (known as shorebirds in North America). Many of the smaller species are often called "sandpipers", especially members of genera Calidris, Tringa and Actitis. Other well-known groups include curlews and snipes. The majority of species eat small invertebrates picked out of the mud or soil. Different lengths of bills enable different species to feed in the same habitat, particularly on the coast, without direct competition for food. [more]

Scopidae

The Hammerkop (Scopus umbretta), also known as Hamerkop,Hammerkopf, Hammerhead, Hammerhead Stork, Umbrette, Umber Bird, Tufted Umber, or Anvilhead, is a medium-sized wading (56 cm long, weighing 470 g). The shape of its head with a curved bill and crest at the back is reminiscent of a hammer, hence its name. [more]

Sebecidae

[more]

Selenichnidae

[more]

Shartegosuchidae

[more]

Shastasauridae

[more]

Shuotheriidae

[more]

Simimyidae

[more]

Simoedosauridae

[more]

Sinemydidae

[more]

Sinoconodontidae

[more]

Sittidae

Sittidae is a family of small birds which has two subfamilies: [more]

Sloanbaataridae

[more]

Solemydidae

[more]

Solenodontidae

Solenodons are , nocturnal, burrowing, insectivorous mammals belonging to the family Solenodontidae. Only one genus, Solenodon, is known, although a few other genera were erected at one time and are now regarded as junior synonyms. The Solenodontidae family is interesting to phylogenetics researchers due to its retention of primitive mammal characteristics; their species resemble very closely those that lived near the end of the age of the dinosaurs. [more]

Songzidae

[more]

Soricidae

Shrews are small, mouse-like of the family Soricidae. Although their external appearance is generally that of a long-nosed mouse, the shrews are not rodents and not closely related: the shrew family is part of the order Soricomorpha. Shrews have feet with five clawed toes, unlike rodents, which have four. Shrews are also not to be confused with either treeshrews or elephant shrews, which belong to different orders. [more]

Spalacotheriidae

[more]

Spheniscidae

Penguins ( Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the southern hemisphere, especially in Antarctica, where they are most well-known for living. Highly adapted for life in the water, penguins have countershaded dark and white plumage, and their wings have become flippers. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend about half of their life on land and half in the oceans. [more]

Sphenodontidae

[more]

Squalodontidae

[more]

Stagodontidae

[more]

Stagonolepididae

[more]

Steatornithidae

The Oilbird (Steatornis caripensis), also known as Guácharo, is a slim, long-winged bird related to the and usually placed with these in the order Caprimulgiformes. It is sufficiently distinctive to be placed in a family (Steatornithidae) and suborder (Steatornithes) of its own; more recent research[citation needed] indicates that it should even be considered a distinct order (which does not yet have a valid taxonomic name). It is found in the northern areas of South America from Guyana and the island of Trinidad to Venezuela, Colombia, Ecuador, Peru and Bolivia in forests and woodland with caves. It is a seasonal migrant, moving from its breeding caves in search of fruit trees. It has occurred as a rare vagrant to Costa Rica, Panama and Aruba. [more]

Stegodontidae

[more]

Stegosauridae

[more]

Stomatosuchidae

[more]

Strigidae

True owls or typical owls ( Strigidae) are one of the two generally accepted families of owls, the other being the barn owls (Tytonidae). The Sibley-Ahlquist taxonomy unites the Caprimulgiformes with the owl order; here, the typical owls are a subfamily Strigidae. This is unsupported by more recent research (see Cypselomorphae for details), but the relationships of the owls in general are still unresolved. This large family comprises around 189 living species in 25 genera. The typical owls have a cosmopolitan distribution and are found on every continent except Antarctica. [more]

Struthionidae

Struthio is a in the order Struthioniformes, in which the ostrich is the only extant species. [more]

Sturnidae

Starlings are small to medium-sized birds in the family Sturnidae. The name "Sturnidae" comes from the Latin word for Starling, sturnus. Starlings occur naturally in the Old World, from Europe, Asia and Africa, to northern Australia and the islands of the tropical Pacific. Several European and Asian species have been introduced to these areas as well as North America, Hawaii and New Zealand, where they generally compete for habitat with native birds and are considered to be invasive species. [more]

Stylinodontidae

[more]

Sudamericidae

[more]

Suidae

Suidae is the biological to which pigs and their relatives belong. Up to sixteen species are currently recognized, including the domestic pig Sus scrofa or S. domesticus. They are classified into between four and eight genera. In addition to numerous species of wild pig, the family includes the babirusa Babyrousa babyrussa and the warthog Phacochoerus aethiopicus. All of the species are found in the Old World, ranging from Asia and its islands, to Europe, and Africa. [more]

Sulidae

The family Sulidae comprises the gannets and boobies. Both groups are medium-large coastal seabirds that plunge-dive for fish. The species in this family are often considered congeneric, placing all in the genus Sula. However, bones of Sula (boobies) and Morus (gannets) at least can in most cases be readily distinguished, and Abbot's Booby has traits of morphology and behavior not found in any other species and appears to be an ancient lineage maybe closer to the gannets than to the true boobies (Friesen et al. 2000). [more]

Sylviidae

The "Old World Warblers", family Sylviidae are a of small passerine bird species; the names sylviid warblers or true warblers may be more appropriate. The Sylviidae mainly occur as breeding species, as the name implies, in Europe, Asia and, to a lesser extent Africa. However, most birds of temperate regions are strongly migratory, and winter in the latter continent or tropical Asia. Many are accomplished songbirds, though perhaps not as much as other warblers or some thrushes. [more]

Tachyglossidae

Echidnas , also known as spiny anteaters, are four mammal species belonging to the Tachyglossidae family of the monotremes, an order of egg laying mammals. Together with the Platypus, they are the only surviving members of that order comprising the only extant mammals that lay eggs. Although their diet consists largely of ants and termites, they are not actually related to the anteater species. They live in New Guinea and Australia. The echidnas are named after a monster in ancient Greek mythology. [more]

Taeniolabididae

[more]

Talpidae

The Talpidae includes the moles, shrew moles, desmans, and other intermediate forms of small insectivorous mammals of the order Soricomorpha. Moles are, to varying degrees, subterranean animals, whilst desmans are aquatic. Talpids are found across the northern hemisphere, in Asia, Europe, and North America, although there are no moles in Ireland or anywhere in the Americas south of northern Mexico. [more]

Tapejaridae

[more]

Tapiridae

A tapir " class="IPA">/t?'p??r/ "ta-pier") is a large mammal, roughly pig-like in shape, with a short, prehensile snout. Tapirs inhabit jungle and forest regions of South America, Central America, and Southeast Asia. There are four species of Tapirs, being the Brazilian tapir, the Malayan tapir, Baird's tapir and the mountain tapir. All four species of tapir are classified as endangered or vulnerable. Their closest relatives are the other odd-toed ungulates, including horses and rhinoceroses. [more]

Tarsiidae

Tarsiers are primates of the genus Tarsius, a monotypic genus in the family Tarsiidae, which is itself the lone extant family within the infraorder Tarsiiformes. Although the group was once more widespread, all the species living today are found in the islands of Southeast Asia. [more]

Tarsipedidae

The Honey Possum (Tarsipes rostratus) or Noolbenger is a tiny marsupial weighing just seven to eleven grams for the male, and eight to sixteen grams for the female—about half the weight of a mouse. Their physical size ranges from a body length of between 6.5 – 9 cm. They have a typical lifespan of between one and two years. [more]

Tayassuidae

Peccaries (also known as javelinas, by the name javali and Spanish jabalí or pecarí) are medium-sized mammals of the family Tayassuidae. Peccaries are members of the artiodactyl suborder Suina, as are swine (Suidae) and possibly hippopotami. They are found in the southwestern area of North America and throughout Central and South America. Peccaries usually measure between 90 to 130 centimetres (3.0 to 4.3 ft), and a full-grown adult usually weighs between about 20 to 40 kilograms (44 to 88 lb). [more]

Teiidae

[more]

Teleosauridae

[more]

Tenrecidae

Tenrecidae (common name tenrecs) is a of mammals found on Madagascar and parts of Africa. Tenrecs are widely diverse, resembling hedgehogs, shrews, opossums, mice and even otters, as a result of parallel evolution. They occupy aquatic, arboreal, terrestrial and fossorial environments. Some of these species can be found in the Madagascar dry deciduous forests, including the Greater Hedgehog Tenrec. [more]

Teratornithidae

[more]

Testudinidae

Tortoises or land are land-dwelling reptiles of the family of Testudinidae, order Testudines. Like their marine cousins, the sea turtles, tortoises are shielded from predators by a shell. The top part of the shell is the carapace, the underside is the plastron, and the two are connected by the bridge. The tortoise has both an endoskeleton and an exoskeleton. Tortoises can vary in size from a few centimeters to two meters. Tortoises tend to be diurnal animals with tendencies to be crepuscular depending on the ambient temperatures. They are generally reclusive animals. [more]

Tetrapodosauridae

[more]

Thalattosauridae

[more]

Thamnophilidae

The antbirds are a large , Thamnophilidae, of passerine birds found across subtropical and tropical Central and South America, from Mexico to Argentina. There are more than 200 species, known variously as antshrikes, antwrens, antvireos, fire-eyes, bare-eyes and bushbirds. They are related to the antthrushes and antpittas (family Formicariidae), the tapaculos, the gnateaters and the ovenbirds. [more]

Theridomyidae

[more]

Therizinosauridae

[more]

Theroteinidae

[more]

Thinocoridae

The seedsnipes are a , Thinocoridae, of small gregarious waders which have adapted to a herbivorous diet. The family is divided into two genera, Attagis and Thinocorus, each containing two species. The family has a South American distribution, in the Andean and Patagonian regions. The relationships with other families within the order Charadriiformes are uncertain, it has been suggested that the Plains Wanderer of Australia, the jacanas and the painted snipes are their closest relatives. The Plains Wanderer in particular has a similar feeding ecology, although differs markedly in breeding biology. The family's common name is misleading, as they do not resemble true snipe, having short bills on small heads, and seeds do not form a major part of the diet. [more]

Threskiornithidae

The Threskiornithidae includes 34 species of large terrestrial and wading birds, falling into two subfamilies, the ibises and the spoonbills. It was formerly known as Plataleidae. The spoonbills and ibises were once thought to be related to other groups of long-legged wading birds in the order Ciconiiformes, including the storks, the herons, and the bitterns. But recent study suggest that they belong to the Pelecaniformes. Whether the two subfamilies are reciprocally monophyletic is an open question. The South American Checklist Committee's entry for the Threskiornithidae includes the following comment "Two subfamilies are traditionally (e.g., Matheu & del Hoyo 1992) recognized: Threskiornithinae for ibises and Plataleinae for spoonbills; because the main distinction has to do with bill shape, additional information, especially genetic, is required to recognize a major, deep split in the family." ([1]) [more]

Thryonomyidae

The genus Thryonomys, also known as cane rats, grass cutters, or cutting grass, is a genus of found throughout Africa south of the Sahara, the only members of the family Thyronomyidae. They are eaten in some African countries and are a pest species on many crops. [more]

Thylacinidae

The animals in the Thylacinidae were all carnivorous marsupials from the order Dasyuromorphia. The only recent member was the Thylacine (Thylacinus cynocephalus), which became extinct in 1936. The other animals in the group all lived in prehistoric times in Australia. [more]

Thylacoleonidae

[more]

Thyropteridae

Disc-winged bats are a small group of bats of the family Thyropteridae. They are found in and South America, usually in moist tropical rain forests. It is a very small family, consisting of a single genus with four species. [more]

Tillotheriidae

[more]

Tinamidae

The tinamous are a comprising 47 species of birds found in Central and South America. One of the most ancient living groups of bird, they are related to the ratites. Generally ground dwelling, they are found in a range of habitats. [more]

Tinodontidae

[more]

Titanoideidae

[more]

Titanosauridae

[more]

Todidae

The todies are a , Todidae, of Caribbean birds in the order Coraciiformes, which also includes the kingfishers, bee-eaters and rollers. The family has one genus, Todus. These are small near passerine species of forests of the Greater Antilles: Puerto Rico, Jamaica, and Cuba with adjacent islands have one species each, and Hispaniola has two, the Broad-billed Tody in the lowlands (including Gonâve Island) and the Narrow-billed Tody in the highlands. [more]

Toxochelyidae

[more]

Toxodontidae

Toxodontidae is an family of notoungulate mammals known from the Oligocene through the Pleistocene of South America, with one genus, Mixotoxodon, known from the Pleistocene of Central America. They somewhat resembled rhinoceroses, and had teeth with high crowns and open roots, suggesting that they often fed on tough pampas grass. [more]

Tragulidae

The nine species of chevrotain, also known as mouse deer, make up the Tragulidae. Chevrotains are small, secretive creatures, now found only in the tropical forests of Africa, India, Sri Lanka, and South-east Asia. They are the only living members of the infraorder Tragulina. [more]

Traversodontidae

[more]

Trichechidae

Manatees ( Trichechidae, genus Trichechus) are large, fully aquatic marine mammals sometimes known as sea cows. The name manatí comes from the Taíno, a pre-Columbian people of the Caribbean, meaning "breast". They contain three of the four living species in the order Sirenia, the other being the dugong, which is native to the Eastern Hemisphere. The Sirenia are thought to have evolved from four-legged land mammals over 60 million years ago, with the closest living relatives being the Proboscidea (elephants) and Hyracoidea (hyraxes). [more]

Triconodontidae

[more]

Trigonostylopidae

[more]

Triisodontidae

[more]

Trilophosauridae

[more]

Trionychidae

Trionychidae is a family which comprises a number of turtle genera commonly known as soft-shell turtles. It consists of some of the world's largest fresh water turtles, though many can adapt to living in highly brackish areas. Members of this family occur in Africa, Asia, North America, and the East Indies. North American members of genus Trionyx were fairly recently[when?] assigned the new genus name Apalone, though they are still listed semi-correctly as Trionyx in some texts. [more]

Tritylodontidae

[more]

Trochilidae

Hummingbirds are in the family Trochilidae, and are native to the Americas. They are among the smallest of birds, and include the smallest extant bird species, the Bee Hummingbirds. They can hover in mid-air by rapidly flapping their wings 12-90 times per second (depending on the species). They can also fly backwards, and are the only group of birds able to do so. Their English name derives from the characteristic hum made by their rapid wing beats. They can fly at speeds exceeding 15 m/s (54 km/h; 34 mph). [more]

Trogonidae

The trogons and quetzals are in the order Trogoniformes which contains only one family, the Trogonidae. The family contains 39 species in eight genera. The fossil record of the trogons dates back 49 million years to the mid-Eocene. They might constitute a member of the basal radiation of the order Coraciiformes. The word "trogon" is Greek for "nibbling" and refers to the fact that these birds gnaw holes in trees to make their nests. [more]

Tropidophiidae

The Tropidophiinae are a of snakes found from Mexico and the West Indies south to southeastern Brazil. These are small to medium-sized fossorial snakes, some with beautiful and striking color patterns. Currently, 4 living genera containing 22 species and one extinct genus with one species are recognized. [more]

Tropiduridae

The Tropiduridae is a family of lizards native to and the West Indies. Most are ground-dwelling animals, and the family includes some lizards adapted to relatively cold climates, including those of the Andes mountains and Tierra del Fuego. Several species give birth to live young. [more]

Tsaganomyidae

[more]

Tupaiidae

The treeshrews (or tree shrews) are small mammals native to the tropical forests of Southeast Asia. They make up the families Tupaiidae and Ptilocercidae and the entire order Scandentia. There are 20 species in 5 genera. Treeshrews have the highest brain to body mass ratio of any animal, even higher than humans[citation needed]. [more]

Turnicidae

The buttonquails or hemipodes are a small family of which resemble, but are unrelated to, the true quails. They inhabit warm grasslands in Asia, Africa, and Australia. [more]

Typhlopidae

The Typhlopidae are a of blind snakes. They are found mostly in the tropical regions of Africa, Asia and the Americas. The rostral scale overhangs the mouth to form a shovel like burrowing structure. The eyes are covered with scales and teeth occur in the upper jaw. The tail ends with a horn like scale. Most of these species are oviparous. Currently, 6 genera are recognized containing 203 species. [more]

Tyrannidae

The tyrant flycatchers (Tyrannidae) are a family of birds which occur throughout North and South America, but are mainly Neotropical in distribution. They are now considered the largest family of birds on Earth, with around 400 species. In every country in the Americas, except for the United States and Canada, they are the most diverse avian family. As could be expected from a family this large, the members vary greatly both in shape, patterns and colors. Some Tyrant flycatchers superficially resemble the Old World flycatchers. They are members of suborder Tyranni (suboscines) that do not have the sophisticated vocal capabilities of the songbirds. [more]

Tyrannosauridae

[more]

Tytonidae

Barn-owls (family Tytonidae) are one of the two of owls, the other being the typical owls, Strigidae. They are medium to large sized owls with large heads and characteristic heart-shaped faces. They have long, strong legs with powerful talons. They also differ from Strigidae in structural details relating in particular to the sternum and feet. [more]

Uintatheriidae

[more]

Undetermined

Upupidae

The Hoopoe , Upupa epops, is a colorful bird that is found across , notable for its distinctive 'crown' of feathers. It is the only extant species in the family Upupidae. One insular species, the Giant Hoopoe is extinct, and the Madgascar subspecies of the Hoopoe is sometimes elevated to a full species. [more]

Uropeltidae

The Uropeltidae are a of primitive burrowing snakes found in southern India and Sri Lanka. The name is derived from the Greek words ura ("tail") and pelte ("shield"), indicating the presence of the large keratinous shield at the tip of the tail. Currently, 8 genera are recognized comprising 47 species. [more]

Ursidae

Bears are of the family Ursidae. Bears are classified as caniforms, or doglike carnivorans, with the pinnipeds being their closest living relatives. Although there are only eight living species of bear, they are widespread, appearing in a wide variety of habitats throughout the Northern Hemisphere and partially in the Southern Hemisphere. That which pertains to bears is called ursine. Bears are found in the continents of North America, South America, Europe, and Asia. [more]

Varanidae

Varanidae is a group of lizards of the Varanoidea. The family is a group of carnivorous lizards which includes the heaviest living lizard, the Komodo dragon, and the crocodile monitor which is the longest lizard in the world. Varanidae contains the living genus Varanus and a number of extinct taxa. Their closest living relatives are the anguid and helodermatid lizards. [more]

Vespertilionidae

Evening bats or, perhaps more correctly, Vesper bats (family Vespertilionidae) are the largest and best-known family of . They belong to the suborder Microchiroptera (microbats). There are over 300 species distributed all over the world, on every continent except Antarctica. Sometimes the family is called "common bats". It owes its name to the latin word vesper, meaning "evening". [more]

Viperidae

The Viperidae are a family of found all over the world, except in Australia, Ireland, Madagascar and the Arctic Circle. All have relatively long hinged fangs that permit deep penetration and injection of venom. Four subfamilies are currently recognized. [more]

Vireonidae

The vireos (sg. pronounced ) are a group of small to medium-sized birds (mostly) restricted to the New World. They are typically dull-plumaged and greenish in color, the smaller species resembling wood warblers apart from their heavier bills. They range in size from the Choco Vireo, Dwarf Vireo and Lesser Greenlet, all at around 10 centimeters and 8 grams, to the peppershrikes and shrike-vireos at up to 17 centimeters and 40 grams (Forshaw & Parkes 1991). [more]

Viverravidae

[more]

Viverridae

The Viverridae is made up of 35 species, including all of the genets, the Binturong, most of the civets, and the four linsangs. [more]

Vombatidae

Wombats are marsupials; they are short-legged, muscular quadrupeds, approximately 1 metre (39 in) in length with a very short tail. They are found in forested, mountainous, and heathland areas of south-eastern Australia and Tasmania. The name wombat comes from the Eora Aboriginal community who were the original inhabitants of the Sydney area. [more]

Wangliidae

[more]

Wynyardiidae

[more]

Xantusiidae

Night lizards ( name Xantusiidae) are a group of very small, viviparous (live-bearing) lizards, averaging from less than 4 cm to over 12 cm long. The family has only three genera, with approximately 23 living species. The genera are divided by geographic range: Xantusia in southwestern North America and Baja California, Cricosaura in Cuba, and Lepidophyma, the most populous night lizard genus, in Central America. [more]

Xenopeltidae

The Xenopeltidae are a family of snakes created to the genus Xenopeltis, which is found in Southeast Asia. Its members are known for their highly iridescent scales. Currently, two species are recognized and no subspecies. [more]

Xenosauridae

The Xenosauridae is a family of native to Central America and China. Also known as knob-scaled lizards, they have rounded, bumpy scales and osteoderms. Most species prefer moist or semi-aquatic habitats, although they are widespread within their native regions, with some even inhabiting semi-arid scrub environments. They are carnivorous or insectivorous, and give birth to live young. [more]

Xiphodontidae

[more]

Yalkaparidontidae

[more]

Younginidae

[more]

Zalambdalestidae

[more]

Zosteropidae

The white-eyes are small birds native to tropical, subtropical and temperate Sub-Saharan Africa, southern and eastern Asia, and Australasia. White-eyes inhabit most tropical islands in the Indian Ocean, the western Pacific Ocean, and the Gulf of Guinea. Discounting some widespread members of the genus Zosterops, most species are endemic to single islands or archipelagos. The Silvereye, Zosterops lateralis, naturally colonised New Zealand, where it is known as the "Wax-eye" or Tauhau ("stranger"), from 1855. The Silvereye has also been introduced to Hawaii as well as the Society Islands in French Polynesia. [more]

At least 197 species and subspecies belong to the Family Zosteropidae.

More info about the Family Zosteropidae may be found here.

References

[ Back to top ]
  1. ^ Benton, Michael J. (1997). Vertebrate Palaeontology. London: Chapman & Hall. pp. 105–109. ISBN 0-412-73810-4. 
  2. ^ www.pnas.org
  3. ^ Stewart J. R. (1997): Morphology and evolution of the egg of oviparous amniotes. In: S. Sumida and K. Martin (ed.) Amniote Origins-Completing the Transition to Land (1): 291-326. London: Academic Press.
  4. ^ Gauthier, J., Kluge, A.G. and Rowe, T. (1988). "The early evolution of the Amniota." Pp. 103-155 in Benton, M.J. (ed.), The phylogeny and classification of the tetrapods, Volume 1: amphibians, reptiles, birds. Oxford: Clarendon Press.
  5. ^ Benton, M.J. (2004). Vertebrate Paleontology. Blackwell Publishers. xii-452. ISBN 0-632-05614-2. 
  6. ^ Laurin, M. and Reisz, R.R. (1995). "A reevaluation of early amniote phylogeny." Zoological Journal of the Linnean Society, 113: 165-223.

Sources

[ Back to top ]
Last Revised: September 22, 2009
2009/09/22 06:21:08