Fabio and others, I checked the Google image that you provided and must say
that the "Pacific Lepton Clam" can be found in much deeper water than 5
meters.  In 2001 I dredged one up in S. Puget Sound attached to a sea mouse
[Aphrodita] from 123 meters depth.

In addition in December 2006 an article in the Dredgings newsletter of the
Pacific Northwest Shell Club has a fascinating story from B.C. Canada.
William Merilees reports finding a commensal crab [Pinnixa faba] with a
small mussel [Mytilus trossulus] attached to its shell.  But the neat part
is that the crab was living inside a purple mahogany clam [Nuttallia
obscuratus (Reeve, 1857)].  N. obscutatus are non-native introduced clams
from Asia which arrived in about 1990 probably in bilge water and are now
the most common bivalves in some locations in N. Washington State and S.
British Columbia, Canada beaches. Marilees reports finding the first example
in May 2000 but repeating the observation twice more in October 2000.  Bert
Bartleson, Olympia, WA, USA

________________________________________
From: Conchologists List [mailto:[log in to unmask]] On Behalf Of
Fabio Moretzsohn
Sent: Tuesday, January 09, 2007 10:02 AM
To: [log in to unmask]
Subject: Re: Bivalves on a crab

I just had the first edition of American Seashells (1954) on my desk, so I
checked it. The figure you are talking about is Fig. 80, on page 396, and it
reads: "Pacific Lepton Clams. a .Pseudopythina rugifera Cpr., 1/2 inch,
attached to the underside of a crawfish".

It is a nice line drawing, and the crawfish does resemble a lobster although
with small claws.

I found two photos of this bivalve on Google Images, and one of the photos
is almost exactly as the line drawing in Abbott 1965: 396. See one photo at:
http://tinyurl.com/y4xcy2

The site says that the bivalve is known as Mud Shrimp Clam, and it is
attached to a Mud Shrimp, Upogebia pugettensis.


Fabio
-------------------------------------------------
Fabio Moretzsohn, Ph.D.
Post Doctoral Research Associate
Harte Research Institute of Gulf of Mexico Studies
Texas A&M University-Corpus Christi
6300 Ocean Drive, Unit 5869
Corpus Christi, TX 78412-5869
Phone: (361) 825-3230
Fax: (361) 825-2050
[log in to unmask]

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