Metacarcinus gracilis

Metacarcinus gracilis
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Brachyura
Family: Cancridae
Genus: Metacarcinus
Species:
M. gracilis
Binomial name
Metacarcinus gracilis
(Dana, 1852) [1]
Synonyms[1]

Cancer gracilis Dana, 1852

The graceful rock crab or slender crab, Metacarcinus gracilis (the naming convention recognized by WoRMS) or Cancer gracilis (the naming convention recognized by ITIS), is one of two members of the genus Metacarcinus, with white tipped chelae (claws). The second crab in the genus to have white tipped claws is M. magister (Dungeness crab).[2] Both of these eastern Pacific crab species are recognized by ITIS as belonging to the much larger genus Cancer. M. gracilis has been caught from Alaska to Bahía Magdelena, Baja California.[3] Although M. gracilis is only found in the Pacific Ocean, it has cousins in the Atlantic Ocean. The genus Cancer (sensu lato) apparently evolved in the Pacific Ocean and later migrated to the Atlantic Ocean.[4] Larvae and small juveniles of this species are often seen riding jellyfish, especially Phacellophora camtschatica. The juvenile crabs steal food from the jellyfish and also clean off parasitic amphipods.[5]

  1. ^ a b P. K. L. Ng; D. Guinot; P. J. F. Davie (2008). "Systema Brachyurorum: Part I. An annotated checklist of extant Brachyuran crabs of the world" (PDF). Raffles Bulletin of Zoology. 17: 1–286. Archived from the original (PDF) on 2011-06-06.
  2. ^ Eugene N. Kozloff (1983). Seashore Life of the Northern Pacific Coast. Seattle: University of Washington Press. ISBN 9780295960845.
  3. ^ J. Dale Nations (1975). "The genus Cancer (Crustacea: Bachyura): systematics, biogeography, and fossil record" (PDF). Natural History Museum of Los Angeles County Science Bulletin. 23: 1–104.
  4. ^ Michelle K. Harrison; Bernard J. Crespi (1999). "Phylogenetics of Cancer crabs (Crustacea: Decapoda: Brachyura)" (PDF). Molecular Phylogenetics and Evolution. 12 (2): 186–199. doi:10.1006/mpev.1998.0608. PMID 10381321.
  5. ^ Trisha Towanda; Erik V. Thuesen (2006). "Ectosymbiotic behavior of Cancer gracilis and its trophic relationships with its host Phacellophora camtschatica and the parasitoid Hyperia medusarum". Marine Ecology Progress Series. 315: 221–236. Bibcode:2006MEPS..315..221T. doi:10.3354/meps315221.