E-Fauna BC: Electronic Atlas of the Wildlife of British Columbia

Placetron wosnessenskii Schalfeew, 1892
Scaled Crab
Family: Lithodidae

Species account author: Josephine Hart.
Extracted from Crabs and their relatives of British Columbia.

© Aaron Baldwin  Email the photographer   (Photo ID #2206)

E-Fauna BC Static Map
Distribution of Placetron wosnessenskii in British Columbia
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Species Information

Carapace flattened, wider posteriorly than long, covered with curved protuberances bordered anteriorly with short bristles and giving the impression of scales. Rostrum triangular and curved downward. Eyestalk short and protected by rostrum. Chelipeds slender, subequal and slightly shorter than walking legs, scaled, with forward-pointing sharp teeth on inner margin of merus and carpus. Hand with spoon-shaped fingers. Walking legs long and stout, scaled and dorsal margin of merus irregularly serrate with sharp teeth. Ventral distal propodus with needle-like movable spines; dactyl with a row of strong movable spines and curved sharp claws. Anterior dorsal part of abdomen flat with some thin calcareous plates which are scaled. The rest of the abdomen is rounded and soft except for a calcareous telson. In the female there is a calcified area on the left side supporting the pleopods.

Size

Carapace: male 61 x 72 mm, female 50 x 53 mm.

Colour

Carapace medially red-brown and laterally grey with dark brown scales. Chelipeds with red-brown or orange scales and grey or turquoise teeth with white tips. Hand orange and tan with dark red-brown area on dorsal palm and some turquoise streaks on fingers. Walking legs: ischium red-brown; merus orange-brown with red-brown and turquoise bands distally and a small patch of scarlet at junction of carpus which is pale turquoise dorsally and orange ventrally with a dark red band medially; propodus similar but with two dark red bands, and a terminal orange band with black ventral spines; dactyl dark red to orange with spines and claw black. Calcified parts of abdomen light brown, the rest olive green. Eyestalk dark brown; cornea brick red. Antennal flagellum red.

Habitat


Subtidal in rocky areas. Very quick moving; therefore, rarely caught in dredges. SCUBA divers can chase them so more have been caught in recent years. Often associated with sea anemones, Metridium senile. The spines on the tips of the walking legs may be an adaptation to life in such a habitat.

Distribution

Range

Aleutian Islands, Alaska, to Puget Sound, Washington; intertidal to 110 m.
Distribution In British Columbia

Widespread.

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
COSEWIC
UnlistedUnlistedUnlistedUnlisted
BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.

Additional Photo Sources

General References


Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2019. E-Fauna BC: Electronic Atlas of the Fauna of British Columbia [efauna.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 22/11/2019 2:00:32 AM]
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