Shell Identification
The shells below are all
Univalves:
These creatures, which are also known as gastropods, have a single, shell
that is usually coiled. They have a distinct head with tentacles and a
rasping tongue (radula). Most of the 105,000 known species in this group
have shells. Half of the species are marine while the remainder is either
terrestrial or fresh water. The sexes are separate in most marine
species. Free-swimming larva emerges from eggs laid into the water.
This larva eventually grows into a shell adult. The average life
expectancy of a gastropod is five years while some have survived to 30
years. They may be carnivorous, herbivorous or parasitic.
Click on photo or name of shell to
go to another page with additional information.
Most of the photos used here and the
descriptions have been developed by Harlan E. Wittkopf, long time part
time resident of our coastline.
Bivalves
Also
known as pelecypods, they are mollusks with two valves joined by a hinge.
Most of the 20,000 species are marine including clams, mussels, oysters
and scallops. About one third of the species live in fresh water. They
lack a head and radial teeth. They feed on microscopic plant life aided
by their gills. The tow shells (valves) are kept closed by strong
muscles. The sexes may be combined in one individual or may be separate.
Most lay their eggs directly into the water. Oysters, clams, and
scallops are a major source of food.
Lion's Paw |
Bay Scallop |
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