''Mithraculus cinctimanus'' (Banded Clinging Crab) is a species of crab in the
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
Majidae
Majidae is a family of crabs, comprising around 200 marine species inside 52 genera, with a carapace that is longer than it is broad, and which forms a point at the front. The legs can be very long in some species, leading to the name "spider cra ...
. It is found in the
Caribbean region
The Caribbean region of Colombia or Caribbean coast region is in the north of Colombia and is mainly composed of 8 departments located contiguous to the Caribbean.sea anemone,
sponge
Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate throug ...
or
coral
Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and ...
.
Description
''Mithraculus cinctimanus'' is a small crab with an oval carapace slightly longer than it is wide. The front third is slightly hairy and the surface of the hind two thirds is roughened by small tubercles. The front edge has several blunt spines. The colour of the carapace is variable often being olive brown with several large creamy patches. The legs have bands of the same colours and their outer segments are hairy. The fingers of the
chelae
A chela ()also called a claw, nipper, or pinceris a pincer (biology), pincer-like organ at the end of certain limbs of some arthropods. The name comes from Ancient Greek , through New Latin '. The plural form is chelae. Legs bearing a chela are ...
do not completely close and have rounded tips. An adult ''Mithraculus cinctimanus'' is about long.
Distribution
''Mithraculus cinctimanus'' is found in the Caribbean region its range including
Florida
Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...
, the
West Indies
The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea that includes 13 independent island countries and 18 dependencies and other territories in three major archipelagos: the Greate ...
Venezuela
Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...
.
Biology
''Mithraculus cinctimanus'' feeds on filamentous green algae growing on rocks. Young crabs are often found living on the surface of the
mushroom coral
The Fungiidae () are a family of Cnidaria, commonly known as mushroom corals or plate corals. The family contains thirteen extant genera. They range from solitary corals to colonial species. Some genera such as ''Cycloseris'' and '' Fungia'' ar ...
'' Ricordea florida''. At this stage of their lives, the carapace is often covered with felt-like red algae which provides the crab with
camouflage
Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...
.
Ecology
''Mithraculus cinctimanus'' is usually found living commensally with a sponge, coral or a sea anemone. The host is often the sun sea anemone ''
Stichodactyla helianthus
''Stichodactyla helianthus'', commonly known as sun anemone, is a sea anemone of the family Stichodactylidae. ''Helianthus'' stems from the Greek words ἡλιος (meaning sun), and ἀνθος, meaning flower. ''S. helianthus'' is a large, gr ...
'' or in deeper water, the anemone '' Lebrunia danae''. On this latter anemone, ''Mithraculus cinctimanus'' is part of an assemblage of commensal
invertebrate
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...
s each occupying its own characteristic position. It is found hiding under the rim of extended pseudotentacles and when these are retracted, it also retreats leaving only its chelae, eyes and the front part of its head exposed. It seldom moves away from the anemone and seems to be immune to the stings produced by its host's nematocysts.