Amerianna papyracea, or the paper physa, is a species of freshwater snail in the family Planorbidae. It is endemic to New Guinea and one small island just off the coast.
Taxonomy Amerianna papyracea was first described by George Brettingham Sowerby II in 1874, though it was originally given the name Physa papyracea. It was not given a type locality, meaning the location of its discovery is unknown.
Description Amerianna papyracea has a nearly cylindrical shell with a short spire. The columella (central axis of the shell) possesses a twisting structure called a plait, though it is barely noticeable. Very small lines called striae may be present. The shell is notably very thin.
Distribution and habitat This species is endemic to the island of New Guinea, with one additional location in Lake Wisdom on the nearby Long Island. Within this lake, individuals were found on algae-covered rocks, usually at depths of .
References