- 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. In the freshwater neritidae,
unlike most freshwater snails where young are born live or hatch directly
from eggs, development involves a planktonic larval
form referred to as a veliger (Tom Eichhorst).
- 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).
- 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)
Vittina coromandeliana (Sowerby I. 1836)
LINK --SEE OTHER NERITES: