This pea crab has
a hard, smooth, oval carapace
width about twice the length, with rounded, setose
lateral margins. The walking legs (legs 2-5) are flattened,
and walking legs have long, plumose setae
along the margins (photo).
The tips of its dactyls
on legs 2-5 are only slightly curved (photo),
of these legs is about the same length as the dactyl
(photo). The inner
margin of the dactyl
of its claw has a distinct tooth (photo).
Color is variable. Carapace
color is dappled dark brown or black, red-brown and greenish-brown on
and ivory or yellow. All the carapace
margins except the posterior one have a lighter border. The chelipeds
and walking legs are pale yellow with greenish-brown patches, which are
reticulated on the carpus
The abdomen is lighter in color (photo).
width to 8 mm for females, 6.5 mm for males.
eburna Wells, 1928
Common name(s): Arenicolid pea crab, Lugworm pea crab
eburna, carapace width
7 mm wide by 3.5 mm long. Found in a burrow of Abarenicola
pacifica on the mudflats of Padilla Bay.
|(Photo by: Dave Cowles,
How to Distinguish from
P. occidentalis and P. schmittii
more than 2x as wide as long and with pointed lateral margins, plus
no tooth on the inner margin of the dactyl
of their chela.
P. tubicola has a propodus
longer than the dactyl
on legs 3-5 and lives in Terebellid
tubeworm tubes. Pinnixa
and P. littoralis have strongly curved tips to
and usually live commensally in bivalves.
Range: Queen Charlotte Islands,
BC, Canada to Puget Sound
Commensal in lugworm burrows.
This species is not often collected.
et al., 1985
General Notes and
abundances, unusual behaviors:
This closeup of the chelipeds
shows the tooth on the inner margin of the dactyl
The legs are flattened, translucent with darker spots or reticulations,
and are fringed with long, abundant plumose setae.
It can also be seen that the dactyls
and the propodus
of the walking legs are of approximately equal length (though the dactyls
are mostly extended downward in this photo and may appear shorter), and
that the dactyls
are nearly straight. Notice that the last leg is much shorter
This view of the underside shows how much lighter the abdomen is, and
also reveals that this individual is a female.
Authors and Editors of Page:
Dave Cowles (2009): Created original page
CSS coding for page developed by Jonathan Cowles (2007)