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Eutrochozoa

(Superphylum)

Overview

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A taxonomic superphylum.

Photos

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Taxonomy

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The Superphylum Eutrochozoa is a member of the Infrakingdom Lophotrochozoa. Here is the complete "parentage" of Eutrochozoa:

The Superphylum Eutrochozoa is further organized into finer groupings including:

Phyla

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Annelida

The annelids, collectively called Annelida (from anellus "little ring"), are a large phylum of animals comprising the segmented worms, with about 15,000 modern species including the well-known earthworms and leeches. They are found in most wet environments, and include many terrestrial, freshwater, and especially marine species (such as the polychaetes), as well as some which are parasitic or mutualistic. They range in length from under a millimeter to over 3 meters (the seep tube worm Lamellibrachia luymesi). [more]

Chordata

Chordates ( Chordata) are a group of animals that includes the vertebrates, together with several closely related invertebrates. They are united by having, at some time in their life cycle, a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail. The phylum Chordata consists of three subphyla: Urochordata, represented by tunicates; Cephalochordata, represented by lancelets;and Craniata, which includes Vertebrata. The Hemichordata have been presented as a fourth chordate subphylum, but they are now usually treated as a separate phylum. Urochordate larvae have a notochord and a nerve cord but these are lost in adulthood. Cephalochordates have a notochord and a nerve cord but no brain or specialist sense organs, and a very simple circulatory system. Craniates are the only sub-phylum whose members have skulls. In all craniates except for Hagfish, the dorsal hollow nerve cord has been surrounded with cartilaginous or bony vertebrae and the notochord generally reduced; hence hagfish are not regarded as vertebrates. The chordates and three sister phyla, the Hemichordata, the Echinodermata and the Xenoturbellida, make up the deuterostomes, one of the two superphyla which encompass all fairly complex animals. [more]

Echiura

The Echiura, or spoon worms, are a small group of animals. They are often considered to be a group of annelids, although they lack the segmented structure found in other members of that group, and so may also be treated as a separate phylum. However, phylogenetic analyses of DNA sequences place echiurans and pogonophorans within the Annelida. The Echiura fossilise poorly and the earliest known specimen is from the Upper Carboniferous (called the Pennsylvanian in North America). However, U-shaped fossil burrows that could be Echiuran have been found dating back to the Cambrian. [more]

Mollusca

Molluscs are animals belonging to the Mollusca. There are around 93,000 recognized extant species within the phylum. Molluscs are a highly diverse group, with representatives of the phylum living across a wide range of environments including marine, freshwater and a variety of terrestrial habitats. [more]

Nemertea

Nemertea is a of invertebrate animals also known as ribbon worms or proboscis worms . Most of the 1,400 or so species are marine, with a few living in fresh water and a small number of terrestrial forms; they are found in all marine habits, and throughout the world's oceans . Nemerteans are named for Nemertes, one of the Nereids of Greek mythology, and alternative spellings for the phylum have included Nemertini and Nemertinea. [more]

Porifera

The sponges or poriferans (from porus "pore" and ferre "to bear") are animals of the polyphyletic phylum Porifera . They are primitive, sessile, mostly marine, water dwelling filter feeders that pump water through their bodies to filter out particles of food matter. Sponges represent the simplest of animals.These are non-motile animals attached to some solid support.They are covered with a hard outer layer or skeleton. With no true tissues (parazoa), they lack muscles, nerves, and internal organs. Their similarity to colonial choanoflagellates shows the probable evolutionary jump from unicellular to multicellular organisms. However, recent genomic studies suggest they are not the most ancient lineage of animals, but may instead be secondarily simplified. There are over 5,000 modern species of sponges known, and they can be found attached to surfaces anywhere from the intertidal zone to as deep as 8,500 m (29,000 feet) or further. Though the fossil record of sponges dates back to the Neoproterozoic Era, new species are still commonly discovered. Their body form is supported by a skeleton of spicules. [more]

Sipuncula

The Sipuncula or Sipunculida, sipunculid worms or peanut worms, are a containing 144-320 species (estimates vary) of bilaterally symmetrical, unsegmented marine worms. Sipunculid worm jelly (???) is a delicacy in the town of Xiamen in Fujian province of China. [more]

At least 462 species and subspecies belong to the Phylum Sipuncula.

More info about the Phylum Sipuncula may be found here.

Sources

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Last Revised: November 18, 2008