In this large, mostly subtidal
hermit crab, the right chela
is larger than the left, and the carpus
of the right chela are very wide and flattened. The carpus of the right
is wider than it is long. There are spines on the dorsal
of the claws. The first and 2nd walking legs have 3 dark
on the dorsal surface and a white stripe on the medial surface of the carpus,
and rows of red spots on the propodus
cornea of the eye is inflated.
Color: orange, brown, and white, with a purplish-blue on the
walking legs. Antennae are orange-brown. Carapace
about 4.2 cm.
Elassochirus tenuimanus (Dana,
Common name(s): Widehand
Eupagurus tenuimanus, Pagurus tenuimanus
|Elassochirus tenuimanus from
depth, Coffin Rocks, Bowman
|(Photo by: Dave
How to Distinguish
Similar Species: Elassochirus
is the only hermit crab genus in this area has a large right cheliped
has a carpus that is wider than long. The other Elassochirus
such as E. cavimanus and E. gilli,
have a propodus to the
right cheliped that is narrower than the carpus.
Bering sea and
Aleutian Islands, Alaska to Washington; northwestern Pacific
Intertidal (rarely) to
Around rocks, mud, sand,
or shell bottoms, but usually near rocks
uses the large right claw to block the entrance to the shell when the
retreats inside (photo).
the claw is bent beneath the body. The hydroid Hydractina
often lives on the shells this hermit crab lives in.
in Washington can be found from August to May. Larvae hatch
to May. Planktonic stages last several months.
1952 (as Pagurus tenuimanus)
and O'Clair, 1998
General Notes and
Observations: Locations, abundances,
The large, flattened right chela is used to seal the entrance of the
shell when the animal withdraws inside. Photo by Dave Cowles,
In this side view the color pattern on the walking legs can be
have rows of red spots. The carpus
has red stripes. The merus
has large areas of purplish-blue.
This individual is scavenging in an Enteroctopus
dofleini midden. Underwater photo by Jim
Nestler, July 2005
Another individual photographed underwater by Kirt Onthank, July
It is living in a leafy hornmouth shell.
The following views of an individual out of its
shell are for an individual of 9 mm carapace(rather, thorax) length
trawled from 135 m depth in the San Juan Channel, 2018
Closeup of the deep eyescale furrows
is a photo of the left side of the rear thorax and abdomen of an
individual out of its shell, showing the small legs 4-5. Photo by Dave
Cowles, July 2018
Authors and Editors of Page:
Dave Cowles (2005): Created original page