Dear Paul,

Since nobody seems to have picked up the gauntlet, let me give it a try.

The description fits unionid subfamily Anodontinae (etymologically and
phyletically characterized by the absence of hinge teeth), and, although
you didn't mention green coloration, the most likely species is Pyganodon
cataracta (Say, 1817).  A "consubfamilial" relative, Anodonta implicata
(Say, 1829) is also in your neighborhood, but it is thick-shelled for an
anodontine ("Floater") and seldom if ever has green coloration.
Furthermore, A. i. prospers only in waterways with easy access to the sea
(the alewife, an anadromous shad relative, is the only known host to the
mussel's parasitic larva), and your pond was apparently impounded.

Of further interest is the steadfast refusal of the malacological community
to acknowledge not one, but two, senior synonyms for A. i., A. fucata
(Dillwyn, 1817) and A. atra Rafinesque, 1820.

As far as I know, there is no proscription against collecting either of
these species - including aliases.

Harry


At 12:02 AM 10/7/00 -0400, you wrote:
>Today I took a drive to a local college to see if I could get some
>Lymnaea snails from the small campus pond, for a friend who wants some.
>I found the pond half drained for some sort of construction work, and
>not a snail in sight anywhere.  What was in sight was at least a couple
>of hundred large mussels, mostly dead, others near the water's edge
>dying.  I don't know much about fresh water bivalves, but these were by
>far the largest I have even seen in the New England area, some of them
>over 6 inches (150 mm) in length.  I brought home about twenty of them.
>They are thin-shelled, fairly fragile, quite inflated, rather pointed at
>one end and broadly rounded at the other.  I know this isn't much of a
>description, but I also know there are not very many northeastern
>mussels that get this large.  Any ideas what they might be?
>Paul M.

Harry G. Lee
Suite 500
1801 Barrs St.
Jacksonville, FL 32204
USA   904-384-6419
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Visit the Jacksonville Shell Club Home Page at:
http://home.sprynet.com/~wfrank/jacksonv.htm

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