''Porcellana sayana'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

porcelain crab Porcelain crabs are decapod crustaceans in the widespread family Porcellanidae, which superficially resemble true crabs. They have flattened bodies as an adaptation for living in rock crevices. They are delicate, readily losing limbs when attack ...

that lives in the western

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

, often as a

commensal Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit fro ...

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 as ...

s. It is red with white spots, and has a characteristic bulge behind each claw.

Distribution

''Porcellana sayana'' is found along the western coast of the

, from

Cape Hatteras Cape Hatteras is a cape located at a pronounced bend in Hatteras Island, one of the barrier islands of North Carolina. Long stretches of beach, sand dunes, marshes, and maritime forests create a unique environment where wind and waves shap ...

(United States) to

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

, including the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

and the

Caribbean Sea The Caribbean Sea ( es, Mar Caribe; french: Mer des Caraïbes; ht, Lanmè Karayib; jam, Kiaribiyan Sii; nl, Caraïbische Zee; pap, Laman Karibe) is a sea of the Atlantic Ocean in the tropics of the Western Hemisphere. It is bounded by Mexico ...

Description

''Porcellana sayana'' is long, and is red, with numerous whitish spots. It may be distinguished from other species by the form of the first pereiopod; the carpus (last segment before the claw) of that leg bears a lobe which projects forwards. It has a fringe of

seta In biology, setae (singular seta ; from the Latin word for " bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. ...

e along the front of its claws, which it uses in

filter feeding Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ...

Ecology

''Porcellana sayana'' lives in shallow water, at depths of up to , among rocks and oyster shells, or as a

of the

s '' Pagurus pollicaris'' and '' Petrochirus diogenes''. Like another porcelain crab, ''

Petrolisthes galathinus ''Petrolisthes'' is a genus of marine (ocean), marine porcelain crabs, containing these extant species: *''Petrolisthes aegyptiacus'' Werding & Hiller, 2007 *''Petrolisthes agassizii'' Faxon, 1893 *''Petrolisthes amoenus'' (Guérin-Méneville, ...

'', ''Porcellana sayana'' is parasitised by the bopyrid isopod '' Aporobopyrus curtatus'', which lives in the porcelain crab's gill chamber.

Taxonomy

''Porcellana sayana'' was first described by

William Elford Leach William Elford Leach FRS (2 February 1791 – 25 August 1836) was an English zoologist and marine biologist. Life and work Elford Leach was born at Hoe Gate, Plymouth, the son of an attorney. At the age of twelve he began a medical appre ...

in 1820 as ''Pisidia sayana''. Its common names include "spotted porcelain crab" and "Say's porcellanid".

References

{{Taxonbar, from=Q4480511 Porcelain crabs Crustaceans of the Atlantic Ocean Crustaceans described in 1820 Taxa named by William Elford Leach