entire carapace is hard (calcified)
on this hermit crab. The walking legs are quite long for
Color is brownish or pink with a reddish iridescent sheen.
width to 2.8 cm.
Common name(s): Splendid
at 100 m depth in San Juan
|(Photo by: Dave
How to Distinguish
Similar Species: The
fully calcified carapace with dorsal spines, with the long legs and
sheen make this species stand out.
Ocean to Puget
Depth Range: 3-412
mud or sand bottoms
shell barely large enough for its abdomen. Often has stinging
on its shell.
1952 (as Pagurus splendescens)
L.W., E. J Kretschmer, J. B Olsen, W. D Templin, K. C Jones, W. S
2002. Development of microsatellite loci in red
king crab (Paralithodes
camtschaticus). Molecular Ecology Notes 2(2):
General Notes and
Observations: Locations, abundances,
This photo is of a female carrying eggs, who abandoned her shell in
the seawater tank. Photo by Dave Cowles, July 2005
A closeup of the head and shield of Labidochirus splendescens.
Photo by Dave Cowles, July 2005
|On a beam trawl in San Juan
100-120 m deep, in
July 2007 we found several Labidochirus splendescens
living in shell-like
formations that appeared to be composed entirely of the Hydroid Hydractinia
is known to frequently live on shells inhabited by hermit crabs, and to
sometimes overgrow the shell. In these cases the hydroid has
overgrown the tiny shell that the shell can no longer be seen (but see
the X-ray images). This shows that the hydroid is capable of
deal of gastropod-like spiral growth around the hermit crab on its
Digital X-rays compliments of Julie Kellogg, DDS and the Tietan Dental
Clinic in Walla Walla.
|Two different Labidochirus
living in Hydractinia.
The smallest Hydractinia was about 1.3 cm long and
the largest was
about 2.5 cm long. The dark marks on these Hydractinia
an artifact of removing the crabs from the shells.
||Here is a view of the "aperture" of the smaller Hydractinia,
seen on the left in the photo at left..
The hydroid is coiled
like a snail but no hard snail shell can be felt even in the "spire" on
the left side.
||Here is the larger Hydractinia,
seen at right in the photo at left. The outer "whorl" of the
flares more widely than normally seen in a gastropod. No hard
shell can be felt even in the "spire" on the left side.
||This X-ray of the Hydractinia
"house" above shows that the posterior half of the "house" is composed
of a fragmented gastropod shell, while the front of the "house" is
The shadowy outline is the edge of the Hydractinia
||This X-ray of the Hydractinia
"house" above shows a similar arrangement, except that the fragmented
makes up only a third or less of the "house". In some
Cnidarian is said to slowly dissolve the shell but this shell looks
fragmented than dissolved. I am guessing that it was
the hermit crab initially took up residence. If that is the
this shell a vastly superior dwelling than it initially was.
|Here is a closeup of the texture of the outside
The hydroid polyps are gone but the hydrotheca remains. This
was not studied until several days after the crab was removed so I do
know if the hydroid was living when collected.
||A view inside the "aperture" of the larger
shows the smooth
inner surface which would have contacted the body of the hermit crab.
||A view of the edge of the "aperture" of the
hydroid shows that
the "house" is composed entirely of hydroid at least along the
is no trace of a calcified shell.
Another example of Labidochirus
splendescens in a shell covered with Hydractinia.
has grown well past the original margins of this shell as well to form
an enlarged, shell-like case for the hermit crab to live in.
Photo by Dave Cowles, July 2016
Authors and Editors of Page:
Dave Cowles (2005): Created original page