Description

 

Most genera in the Neritidae are amphibious. Nerita species are high-tide shore dwellers. They live either on rocks or mangrove trees. About 50 species are known, largely found in the tropics. In the superfamily, Neritoidea, most are operculate, except  Helicina. In the Helicinidae fanily, the operculum is shell-like, with a short projection.  Theodoxus, is found mainly in or near freshwater streams, as are Clypeola, and Septaria. The latter two closely resemble slipper limpets and have only a rudimentary operculum. The Neritopsidae, another  freshwater family, lives in or near streams like Theodoxus, above.

 

The superfamily, Neritoidea, is remarkable in that it represents a transition line between Vetigastropoda and the more specialized Sorbeconcha clades. Several families show specific and quite evolutionarily advanced features; e.g., reproduction by internal fertilization, with penis and oviduct equivalents, and, air-breathing features. Species in the Helicinidae and Hydrocenidae families, for example, possess a lung chamber and vascular plexus for absorbing oxygen directly from air (see Pulmonate Snails), along with renal specializations for living on land. Neritodryas while technically amphibious is also adapted to terrestrial living.

 

Several species among the Neritidae are also notable in that heritable phenoplastic responses to the environment have been demonstrated as a factor in speciation. Such phenoplastic switching may also underlie the numerous colormorphs of this species (T. Eichorst, personal communication).

 

 

Classification

Class: Gastropoda

Clade: Cycloneritimorpha

Superfamily: Neritoidea

Family: Neritidae

 

Major Genera

• Genus: Clypeola
• Genus: Nerita
• Genus: Neritilia
• Genus: Neritina
• Genus: Neritodryas
• Genus: Puperita
• Genus: Septaria
• Genus: Smaragdia
• Genus: Theodoxus
• Genus: Vittina

Nerita polita subspecies antiquata (Récluz, 1841)
Ancient Nerite
Northern Australia

Vittina coromandeliana (Sowerby I. 1836)
Coromandel-Wood Nerite