''Calcinus morgani'', commonly known as Morgan's hermit crab, is a species of

hermit crab Hermit crabs are anomuran decapod crustaceans of the superfamily Paguroidea that have adapted to occupy empty scavenged mollusc shells to protect their fragile exoskeletons. There are over 800 species of hermit crab, most of which possess an a ...

in the family

Diogenidae The Diogenidae are a family of hermit crabs, sometimes known as "left-handed hermit crabs" because in contrast to most other hermit crabs, its left chela (claw) is enlarged instead of the right. It comprises 429 extant species, and a further 46 e ...

found in the Indo-West Pacific region, the type locality being Indonesia.

Description

This hermit crab has a shield 1.15 to 1.4 times as long as it is broad. The rostral lobe is triangular and the lateral projections very small and blunt. The eye-stalks have inflated bases and are nearly as long as the shield. The left

cheliped A chela ()also called a claw, nipper, or pinceris a pincer-like organ at the end of certain limbs of some arthropods. The name comes from Ancient Greek , through New Latin New Latin (also called Neo-Latin or Modern Latin) is the revival ...

(claw) has four to six robust calcified teeth on its cutting edge and the dactyl has two to four teeth on its cutting edge. The right cheliped is somewhat smaller with fewer teeth. The surfaces of both are dotted with small tubercles and low protuberances. The third pair of

pereopod The decapod (crustaceans such as a crab, lobster, shrimp or prawn) is made up of 20 body segments grouped into two main body parts: the cephalothorax and the pleon (abdomen). Each segment may possess one pair of appendages, although in various g ...

s (walking limbs) have a brush of setae (bristles) near the claw while the other pereopods have scattered setae. The shield is whitish with dark brown margins, the eye-stalks are bright blue with brown bases, the antennal appendages are dark brown and orange, the chelipeds are dark brown with white tips and white tubercles, and the pereopods are dark brown with white bands near the claws. This hermit crab was at one time thought to be synonymous with ''

Calcinus gaimardii ''Calcinus'' is a genus of hermit crabs in the family Diogenidae, containing the following species: *'' Calcinus albengai'' Poupin & Lemaitre, 2003 *'' Calcinus anani'' Poupin & McLaughlin, 1998 *''Calcinus argus'' Wooster, 1984 *''Calcinus c ...

'' but that species has the front half of the shield dark brown and lacks the bright blue on the eye stalks which are entirely orange, apart from a little blue on the corneas.

Distribution and habitat

''Calcinus morgani'' is found in the tropical and subtropical Indo-Pacific region, its range extending from Madagascar to western, northern and eastern Australia, the Philippines, Indonesia and other western Pacific island groups. It is typically found in the

intertidal zone The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species ...

of coral reefs and on rocky shores exposed to strong wave action. This is in contrast to ''C. gaimardii'' which prefers sheltered inlets and is found subtidally.

References

External links

* * {{Taxonbar, from=Q13448469 Hermit crabs Crustaceans described in 1999