Hi Paul and Nora,
I just finished reading the rest of my e-mail and read Paul's
explanation of what this bivalve is. Although I have not seen
a photo of the Japanese shell, it seems like a more likely
one than a shell from the warm Baja and California area. I'd
say it's definitely an introduced Nuttallia of some kind.

You're right, we do have alot of introduced species in our
area, and not just molluscs.
It's really too bad as often they overrun the area and
out-compete the native species. Sometimes you can go to an
area and all you see is the introduced species:
Nuttallia sp has all but whiped out the native Macomas in
areas that used to be filled with them,
There are Tapes philippinarum and Battillaria everywhere,
European Starlings and sparrows comprise most of the small
birds we see in our area (the foothold the introduced Mynahs
had is lessening, though),
Our local species of squirrel and chipmonk have been pushed
out by the big black and grey introduced ones in some areas,
There are goldfish and Red-eared slider turtles in our ponds,
Our lakes are filled with Eurasian Millfoil weeds,
Etc...I could go on, but won't...




>Hi Nora,
>It sounds like Nuttalia obscurata Reeve, a species of Sanguinolariidae (or
>Psammobiidae) introduced into that area from japan, and common there in some
>areas.
>Regards,
>Paul M.
>
>
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Peter Egerton, Vancouver, Canada
Collector of worldwide Mollusca
http://www.intergate.bc.ca/personal/seashell/index.html
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