Comprehensive Description

Siphonaria is a genus of gastropod mollusks, one of the three genera in the family Siphonariidae. Siphonariids resemble true limpets (family Acmaeidae), but do not have true gills. Instead, siphonariids have either secondary gills in the mantle cavity, or the mantle cavity serves as both a lung and a generalized gill. Siphonariids live on rocks close to the high tide line, where they can remain wet. Siphonariid eggs are laid in jellylike strings near the water's edge. Upon hatching, the young pass through a brief free-swimming stage before settling on rocks near the high tide line. (Rehder 1981)