Chorilia longipes Dana, 1851

Common name(s): Longhorn decorator crab

Synonyms:
Phylum Arthropoda
Subphylum Crustacea
Class Malacostraca
Subclass Eumalacostraca
Superorder Eucarida
OrderDecapoda
Suborder Pleocyemata
Infraorder Brachyura
Family Majidae
Chorilia longipes from 100 m depth, San Juan Channel.  The carapace of this individual is 2.5 cm wide and 4.5 cm long, including rostrum.  The total leg span in a normal stance is 14 cm.
(Photo by: Dave Cowles, July 2007)
Description:  This Majid crab has a long rostrum (over 1/2 as long as the rest of the carapace) composed of 2 slender, spinelike processes (photo).  The processes are diverged from one another throughout most of their length.  There is no promenent spine projecting laterally behind each eye (photo), though there is is smaller spine forming the back half of the eye orbit and a forward-projecting spine in front of the eye at the base of the rostrum.  The carapace is pear-shaped, white with orange spines, with a width to 4.5 cm.  The legs are long, fairly smooth, red with white bands, and rounded in cross-section.  There are 2 white bands on the merus and 1 each on the carpus and on the propodus.  The first walking leg is longer than the chelipeds.

How to Distinguish from Similar Species:Oregonia gracilis has rostral spines which are nearly parallel at least proximally, it has a prominent spine projecting laterally behind each eye (photo), and it does not have spines on the dorsal carapace.

Geographical Range:  Kodiak, Alaska to Cortez Bank, Mexico; Japan.

Depth Range:  subtidal, 9-1190 m

Habitat:  Rocks and boulders, gravel, shelly, and muddy bottoms.

Biology/Natural History:  This species often decorates.  The individual above has several sponges on it.



 

References:

Dichotomous Keys:
  Coffin, 1952
  Hart, 1982
  Kozloff 1987, 1996
  Wicksten, 2009
 

General References:
  Jensen, 1995

Scientific Articles:
Berke, Sarah K. and Sarah A. Woodin, 2009.  Behavioral and morphological aspects of decorating in Oregonia gracilis (Brachyura Majoidea).  Invertebrate Biology 128:2 pp 172-181

Web sites:


General Notes and Observations:  Locations, abundances, unusual behaviors:



Though there are many bumps and small spines on this species' carapace, it does not have the prominent, laterally-directed spines behind the eyes that Oregonia gracilis has.



The long spines which make up the rostrum can be clearly seen from below


Chorilia longipes has long, thin legs and chelae.  Both of its chelae are striped orange-red and white on both the inside and outside.
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Left chela, inside view
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Left chela, outside view
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Right chela, outside view



Authors and Editors of Page:
Dave Cowles (2007):  Created original page
CSS coding for page developed by Jonathan Cowles (2007)