One type of Paguroidea is the Coenobita rugosus. They look fundamentally the same as the Ecuadorian crabs with the exception of a couple of key contrasts. The Ruggie or rugosus comes in a wide range of hues: black, tan, blue, peach, gray and even white.

In any case, Ecuadorian crabs have more variety of shading, for example, darker-hued feet, though the body of a ruggie is the same, uniform shading.

Just like Ecuadorian crabs, the Ruggie has striping on the sides of its body and longer eyes. Search for orange antennas, sandy-hued eyestalks, and little, corner to corner lines, “line marks”, on its hook. Albeit Ecuadorian crabs have these imprints too, they are normally more articulated on ruggies.


Coenobita rugosus (the “brownish hermit crab”) is the latest types of extraordinary land hermit crab to touch base in the U.S. Coenobita rugosus is local to the Pacific islands also and keeping in mind that many people had known about them when the very first rugosus arrived in the U.S.,


NameCoenobita rugosus 1837, H. Milne Edwards.
Scientific NamePaguroidea
SynonymsCrying Land Hermit Crab, Coenobita rugosa H. Milne Edwards, 1837. Tawny Hermit Crab, Coenobita rugosa var. wagneri Doflein, 1900. Spot-handed Hermit Land crab, Terrestrial Hermit Crab, Coenobita subrugosa Neumann, 1878

Vernacular names of Paguroidea

  • English: Ruggie Hermit Crab
  • Spanish: Ermitaño de playa
  • Thai: ปูเสฉวนบกเล็ก
  • Japanese: ナキオカヤドカリ
  • Chinese: 灰白陆寄居蟹


History about the Paguroidea is given below:

Origin of Paguroidea

A wide range of species of Coenobita rugosus lives in tropical regions of the Indo-Pacific locale, the western Caribbean and the western Atlantic.

Fossil records

The fossil record of the Crustacean is uncommonly great, extending back to the Cambrian. Nonetheless, they don’t show up in any plenitude until the Carboniferous.

The primary undoubted Crustaceans are Perspicaris and Canadaspis which have a place with the Subclass Phyllocarida. They were mainly present in the Middle Cambrian Burgess Shale.

Through the Carboniferous, the various real gatherings of Crustaceans are available aside from the Eucarida. The greater part of these fossils is found inside shallow sea sediments in light of the fact that these offered great potential for conservation.

The Eucarida showed up in the Mesozoic, however, they had their birthplaces in the Carboniferous or Devonian. The Eucarida, particularly the Decapoda, experienced a versatile radiation amid the Jurassic, with the presence of present-day shrimps and crabs.

The lobsters and crabs carried on broadening to end up one of the real groups of aquatic life animals. Hermit crabs are an uncommon group that looks for security inside disposed of mollusk shells. Loner crabs are also known at least from the Cretaceous Speeton Clay where hermit crabs occupied void ammonite shells.

Distinctive Features Of Paguroidea

  • The body color of Paguroidea varies. Cream, brown, dark-blue, bluish-gray, dark brown, pink, reddish-orange, or mixture of many colors with spots on the entire body.
  • Dorsal surface with dark “O” shape mark on the front of its shield.
  • Dark colored or black slanting (/) stripes behind the bases of an antenna, on adjacent borders of a shield.
  • Eyestalks are compressed and flattened in shape. They are yellow-brown or white in color. There is also a black to dark green band on lower surfaces of the eyeballs.


  • Antennal icicles are attached with the second segment of peduncle. The lower part of an antenna is light orange or light yellow.


  • The left cheliped of Coenobita rugosus is larger than right cheliped. They have a series of seven edges on the upper external surface palm of left cheliped.
  • The upper borders of both cheliped with a brush of setae.
  • The palm of left cheliped is four-cornered in an outward form and the outer lower surface with a dark color patch in adult Coenobita rugosus.

Walking legs of Coenobita rugosus

  • The horizontal surface of dactylus, propodus of left third walking leg flattened.
  • The outer surface of propodus of a left third walking leg is detached from the dorsal surface by a well-marked longitudinal top.


  • The abdomen of Coenobita rugosus is short.


  • The size of Paguroidea can reach the length of 19mm.

Hermit crab without a shell

At the point when right size and shape of gastropod shells are not accessible, Coenobita rugosus have been known to a choice of wearing different objects, for example, tree nut structures or bits of shoreline litter instead of going unprotected.


This has turned out to be exceptionally common in a few zones, do not completely to the expanded predominance of marine waste and jetsam. Moreover, due to the reduction of seashells from shorelines because of people gathering them.

Geo-distribution of Paguroidea

Geo-distribution is from India to the Pacific Ocean. Then from East Africa to the Philippines. Then it also covers Taiwan and Ogasawara Islands in Japan.


Hermit land crabs have exoskeleton structure of body which means they have shells.

The body of a tawny hermit crab demonstrates topsy-turvy morphology, which might be identified with use of the dextral shell. According to sources, researchers analyze the impact of the shell.

They raised Pagurus filholi from the glaucothoe stage to full-sized grown-ups, in a straight tusk shell, in a sinistral shell, without its shell, and in an ordinary dextral shell as a control.

Body parts of hermit crab that demonstrate the most obvious asymmetry, pleopods, chelipeds, and uropods, were checked at the season of the shedding of exuviae amid raising. No reversal of laterality on these characters was watched.

Moreover, in hermit crabs subjected to circumstances other than a dextral shell, the generally rather short right uropod turned out to be to some degree broadened. Although, in those raised in sinistral shells, the correct major cheliped was more augmented.

Ecology of Paguroidea

Seen in the wild sheltering under leaf litter amid the day and bolstering nocturnally during the evening. Hermit land crabs also move in a few locales, however, does not climb or move as high as C. cavipes.

In territories where cavipes is absent, hermit crabs will utilize tree gaps to swap shells or to refill their shell water. Loner crabs will enter times of latency in mangrove tree openings.

They can take up water from soggy sand. Moreover, regardless of happening close to the ocean, it is hesitant to enter the salt water, and will in inclination fill its shell with new water.

Food Habits

Furthermore, in the wild, Coenobita rugosus are hunters. Along these lines, they are “hard-wired” to seek out the widest possible variety of foods. Their regular eating regimen incorporates plants, fish, meat, even fecal matter, and ocean growth.

Since they look out such a variety of foods, specialists currently trust that land hermit crabs will essentially decide not to gobble anything instead of filling up on the food that they have just eaten once in the previous few hours.

They have found eating tortoise feces and algae in the wild.

Paguroidea Habitat

They live in marine and terrestrial parts. Wrinkled Land Hermit Crabs live on sandy beaches. You can also find them under bushes and in debris during the day.

  • The range of depth is based on 1 case in 1 taxon.
  • A temperature of water and chemistry ranges is also based on one sample

Ecological ranges are given below:

  • Temperature range (°C): 2.059 – 2.059
  • Depth range (m): 2253 – 2253
  • Nitrate (umol/L): 34.704 – 34.704
  • Oxygen (ml/l): 3.332 – 3.332
  • Salinity (PPS): 34.748 – 34.748
  • Silicate (umol/l): 140.785 – 140.785
  • Phosphate (umol/l): 2.389 – 2.389


Hermit crab has a normal life expectancy of 15 to 20 years in the imprisonment. Few land hermit crabs, for example, Coenobita brevimanus, can last for 12 to 70 years.



The Coenobita rugosus (PAGUROIDEA) just needs to rarely dunk in rainwater or either in the ocean to keep its chambers wet. Females, still, must go to the edge of the ocean to discharge their eggs into the ocean water. Then these eggs hatch into planktonic hatchlings.

hermit crab

At the point when the larvae form into a little hermit crab, it finds an unfilled shell at that point heads landward. These hermit crabs change their shells routinely but just then, when they locate a bigger and more up to date shell to feel safe in.

Communication & Reception

“Hermit crab”, the name is a misnomer. Land recluse crabs are extremely social animals who live in states of at least 100 in the wild. Although, they don’t toll well as lone pets. These crabs speak with one another by means of twittering sounds known as stridulation.

Moreover, these creatures spend significant time (weeks or months) shedding below ground. They keep them in gatherings of at least three will support these pets from being desolate or discouraged. The worry of being separated from everyone else can have genuine health effects.

Known Hazards

Known threats to hermit crabs are given below:

  • Coastal contamination is so awful in a few regions that hermit crab populaces are ceasing to exist.
  • A few kinds of hermit crabs were over-picked for the pet marketplace. A precedent is in Australia, where just the Australian Land Hermit Crab is currently legitimately permitted to be sold as a pet since people requested an excessive number of different sorts.
  • The over-gathering of strawberry hermit land crabs meant they turned out to be excessively uncommon, making it impossible to discover in their natural habitat.
  • The pet market has named these tiny hermit crabs as adorable and provided bunches of charming painted shells for them to live in. The issue with painted shells is that in the long run, the paint chips off, and the crabs can be harmed by it when they eat it. Numerous crabs have died after picking a painted shell to live in.
  • One of the greatest dangers for hermit crabs is being eaten by seagulls. Many hermit crabs have a rapid reflex when a dark shadow falls over them, and they will hide into their shells to guard and cover themselves from the flying birds.

Hermit Crab Similar Species

Hermit Crab Fun Facts

Apart from all the hazards, there are also some fun facts about the Paguroidea:


Although, these fun facts are quite interesting yet there are some dangers as well.



Aymen Nizam

Aymen Nizam

I am IT (Graduate) from Bahria University Islamabad currently writing blogs on animals and plants, I am a content writer by profession and passionate about writing all information about living things. TapeDaily has provided me a chance to share my expertise with you.

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