Four-tooth Nerite
Nerita versicolor
Funiculate Nerite
Nerita funiculate
Ornate Nerite
Nerita scabricosta
Yellow-banded Nerite
Theodoxus luteofasciatus
The Nerites belong to the Neritidae Family which are small to medium sized shells found in marine, brackish, and freshwater environments, as well as on land. They derive their name from Nerites, a sea deity in Greek mythology. They are thick solid shells that are globular in shape with a low spire and a toothed aperture. Their operculum is calcareous with a semi-circular profile with most having a have a hook that facilitates in closing the shell tightly to seal in moisture when exposed to air. The Nerites are often brightly colored, in a variety of patterns with the exterior of the shells being smooth or patterned, usually by ridges running lengthwise or along the whorls; the interiors are smooth.
Nerites live attached to hard surfaces such as rocks or wood and are found in the intertidal zone to the low tide line. They feed by grazing on algae, detritus and diatoms. In turn they are preyed upon by shore birds, crabs, and predatory mollusks. They are found in tropical and temperate seas, worldwide. There are three hundred fifty global species in the Neritidae Family of which five are found in coastal waters of the Baja.