Assimineidae is a family of minute snails, also known as palmleaf snails, with an operculum, gastropod mollusks or micromollusks in the superfamily Rissoidae. Many of these very small snails live in intermediate habitats, being amphibious between saltwater and land; others live in freshwater.

Distribution

The distribution of the Assimineidae is worldwide. The oldest fossils are known from the Cenomanian aged Burmese amber.

Ecology

Various species in this family occur in estuarine habitats, in salt marshes and in freshwater. Some are terrestrial or amphibious.

Description

The shell is small to medium large, more or less egg-conelike shaped. The apertural margin is simple. The operculum is in most cases horny. Species in this family are characterized by rudimentary cephalic tentacles, a trunklike snout, a foot with a groove and rudimentary to absent ctenidium (a comb-like respiratory apparatus).

Taxonomy

The following three subfamilies were recognized in the taxonomy of Bouchet & Rocroi (2005):

Genera

Genera in the family Assimineidae include: Genus † Laternoides W. Yu & Y.-H. Xi, 1977 subfamily Assimineinae subfamily Ekadantinae subfamily Omphalotropidinae Thiele, 1927 (synonym: Garrettiinae Kobelt, 1906 )