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

Emerita analoga (Stimpson, 1857)
Mole Crab; Pacific Mole Crab; Sand Crab
Family: Hippidae

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

© Marjorie Wonham  Email the photographer   (Photo ID #95937)

E-Fauna BC Static Map
Distribution of Emerita analoga in British Columbia
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Species Information

Egg-shaped. Carapace marked on anterior half with fine transverse striations; front tridentate. Eyestalk long and slender with a small, terminal cornea. Antennules slender and setose. Antennal flagella long and robust with double rows of plumose setae which are hidden beneath mouth parts except when animal actively feeding. First 4 pairs of pereiopods greatly modified and used for digging. They are heavily bristled, flattened and curved and not chelate. 5th pereipod slender and chelate and used for cleaning as in other Anomura. Abdominal segments decrease in size posteriorly; telson large and arrow-head shaped. Uropods well developed but pleopods only in females; three pairs.

Size

Carapace: male 22 mm, female, 35 mm.

Colour

Carapace greenish or steel grey dorsally with fine cross stripes of lighter colour, or pink, anteriorly; posteriorly two white dots on light coloured mid-dorsal with pale pink laterally. First pereiopod shell pink and white; the rest mostly pink with some pale iridescence. Abdomen grey with 6th segment and telson white, with two pink stripes.

Habitat


Sandy beaches with heavy surf. These crabs bury themselves backwards in sand quickly to avoid being swept away by surf or current. On wet sand they move backwards leaving a typical track. They feed when almost completely submerged, by unfurling the net made by the antennal flagella which filters plankton from the sea water.

Distribution

Range

Records from Karluk, Kodiak Island, Alaska, Wickaninnish Bay, Vancouver Island, and Kalalock Beach, Washington. All these appear to be individuals of a temporary invasion by planktonic larvae drifting north. They are not found regularly in these localit
Distribution In British Columbia

In the sand of Wickaninnish Bay, Vancouver Island, between 1958 and 1960, there were many individuals, but in 1961 I found only one large cast shell and I know of no record since. Old-time residents in the area tell of earlier invasions.

Comments


This species occurs in tremendous numbers in southern numbers and is harvested for fish bait. Despite considerable research done by a number of people, the life history of this interesting species is still not at all clear.

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) 2017. 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: 21/07/2017 1:33:38 PM]
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