At 08:04 PM 12/31/1999 -0500, you wrote:
>Dear Conch-L Friends (currently spanning two centuries):
>This is a delightful site.  If you do not know U.S. freshwater molluscs,
>please look at this, it will convince you these are great shells.
>p.s. Martin: P. capax is indicated as coming from southwest Missouri, it
>never has been found there.  Do you mean southeast Missouri?, and the
>pictured Proptera leptodon is a shell of P. fragilis.
>Peace and great shells to you in the upcoming century.
>
>Alan Gettleman
>Merritt Island, FL
>


Nice site!

Potamilus capax (and all Potamilus) lack mantle flap lures. The figured
specimen is probably Lampsilis cardium, which often resembles capax in shell
characteristics. And I agree with Alan, the leptodon is a fragilis. A good
way to tell them apart is the lateral teeth. In fragilis there is one in
left valve and two in the right; in leptodon that is reversed.


G. Thomas Watters
Ohio Biological Survey &
Aquatic Ecology Laboratory
Ohio State University
1315 Kinnear Road
Columbus, OH  USA
v: 614-292-6170
f: 614-292-0181