Hi Fabio and others

Like David I am pretty sure the first specimen is not a viviparid. I
would be more willing to bet that the specimen is a very small
juvenile of the Melanoides otherwise it is a hydrobiid. I am
currently in Sydney and do not have access to specimens from Mexico to compare.

Regards

Stephanie

At 03:25 AM 15 03 2012, you wrote:
>Viviparids will be much larger than hydrobiids in maximum size.  The
>specimen has enough whorls to be reasonably mature.  I see that size
>information is listed as not available, but hopefully they at least
>know whether that photo was taken at high magnification or not.
>
>I don't offhand know of any tall-spired viviparids in southern Mexico.
>  It could also be a land snail that fell into the cenote.
>




Dr Stephanie A. Clark

Director
Invertebrate Identification Australasia
6535 N Mozart St, Apt 3F
Chicago, IL, 60645-4339 USA
Mobile 1 (205) 310 9942

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