Hello,

The snail appears to be a Chinese or Japanese mystery snail. Both are invasive species, and they can be very abundant in some lakes.  Here is some additional information from the GLANSIS website:

Please e-mail Rochelle Surtevant (the GLANSIS data base coordinator) and me (Dan O'Keefe) with some additional details such as lake name and collection location.  Also, if you could attach any images that you have it would be helpful for Rochelle to see them and determine if they are Chinese or Japanese mystery snails.  They look like Chinese snails to me, but I have not seen the Japanese species in person and there is only a slight difference in shell shape.

Contact info for follow up e-mail:

Hope this helps,

Dan