What is "thysanophoridae"

Thysanophoridae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Helicoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).

These are common woodland snails of North America. They also occur in a few recorded spots in South America.

This family is defined by the absence of both a diverticulum and a stimulatory organ.