09 May 2010

Saturday's snails

Yesterday I went on a field trip with Tim Pearce in a park in Virginia along the Potomac River. Our main quarry was a land snail called Xolotrema denotata. The only published record of X. denotata from that area dates back to 1910. So we thought it would be worthwhile to relocate the species.

Here are some of the snails we saw.

Ventridens ligera (left) and Mesodon thyroidus are probably the 2 two most common native species along the Potomac. Live snails, like these 2 I photographed yesterday, can be abundant even in the floodplains of the river. How they survive the floods is a mystery.

The snail on the left with the hairy shell and the long parietal tooth in the next picture is a Stenotrema sp., either S. barbatum or S. hirsutum. If you know how to tell the 2 apart, let me know. I can't identify the other snail, which was probably a juvenile.

As for Xolotrema denotata, we couldn't find any. It is possible that X. denotata doesn't live on or near the floodplain where we did all of our searches. So it may be worthwhile to return to the area on another occasion.


Koráb said...

Stenotrema looks exactly like european Isognomostoma, and if I would find snail like the second one here in Europe, I would consider it to be a carnivorous Oxychilus, living as well as Isognomostoma under fallen trees

Koráb said...
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