margarites

Margarites is a genus of small sea snails in the family Margaritidae, marine gastropod mollusks within Vetigastropoda. The name derives from Greek margarites, meaning pearl, a reference to the often nacreous interior of the shells. The genus comprises numerous species distributed mainly in cold northern waters.

Shells of Margarites are typically low-conical to trochiform, often only a few millimeters to over a centimeter in diameter. They commonly have rounded whorls with subtle to strong spiral sculpture; the outer surface is usually pale, sometimes with brownish markings. The aperture is rounded, and the operculum is calcareous.

Distribution and habitat: Margarites species are found in cold northern oceans, including Arctic and subarctic regions and the North Pacific and North Atlantic. They inhabit subtidal zones on rocky substrates, often in crevices, under stones, or among algal holdfasts, from shallow depths to deeper waters.

Ecology and biology: They are grazers that feed on microalgae, diatoms, and biofilm on exposed rocks. Reproduction is sexual, and many species release free-swimming veliger larvae, though life histories vary by species.

Taxonomy and diversity: Margarites is a relatively speciose genus within Margaritidae, with many described species and several fossils. Due to variation among sources, the exact rank and composition of Margaritidae and related Vetigastropoda have been revised as molecular data accumulate.