At 04:01 PM 8/22/99 -0700, Art Weil wrote:
>Dear Lynn, et al:
>        I keep hearing that there are this or that many extinctions occuring
>every month, day, year (take yer pik). Are there any marine mollusks
>that have become extinct recently?
>        Art

Dear Lynn, Art, and all,

One case of extinction of a marine mollusk was documented by Carlton et al
(1991, The first historical extinction of a marine invertebrate in an ocean
basin: the demise of the eelgrass Lottia alveus. Biological Bulletin 180:
72-80). Carlton and his colleagues attributed the extinction of the
eelgrass limpet, "the first marine invertebrate known to have become
extinct in historical time", "to the catastrophic decline of [the eelgrass]
Zostera in the early 1930s in the North Atlantic Ocean." The eelgrass
limpet used to be found from Labrador to New York; the last known specimens
were collected in 1929. The paper shows the importance of a well-designed
project combining field work (search for limpets in several locations along
the former range of the species) with museum studies (examination of
malacological collections of 14 major museums in the US and Canada). It
serves also as a classical example of demise of a species due to habitat
destruction; other marine, terrestrial, and freshwater species may have
undergone unnoticed extinction in historical times (or even as you read
this note), for the same reason. In case you find difficult to get a copy
of the paper, Gary Vermeij, one of its coauthors, commented on it in his
great autobiography "Privileged Hands".

Best to all,

Jose
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Jose H. Leal, Ph.D.
Director, The Bailey-Matthews Shell Museum
Editor-in-chief, THE NAUTILUS
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