Osteriidae

The Osteriidae is a family of small to medium-sized sea snails, specifically marine gastropod mollusks, belonging to the superfamily Trochoidea. This family is primarily distributed in the Indo-Pacific region, with some species extending into the Atlantic Ocean. Members of Osteriidae are characterized by their relatively small, globular to conical shells, which are often smooth or finely sculpted with axial ribs or spirals. The shell aperture is typically oval or rounded, and the columella is usually thickened and sometimes folded.

Osteriidae snails inhabit shallow to moderately deep marine environments, often found in coral reefs, seagrass beds, and sandy or rocky substrates. They are generally scavengers or detritivores, feeding on organic debris and small particles. Some species may also exhibit a degree of herbivory, consuming algae or other plant matter. The family includes both free-living species and those that may associate with other organisms, such as sponges or corals.

The taxonomy of Osteriidae has undergone revisions, and the family is sometimes considered part of broader classifications within Trochoidea. Notable genera within the family include *Ostrea*, though it is important to note that *Ostrea* is more commonly associated with oysters in the family Ostreidae. True Osteriidae genera include *Ostrea* (in a restricted sense), *Ostrea* (sensu stricto), *Ostrea* (as a subgenus), and others like *Ostrea* (misidentified in some older sources). Modern classifications often place these snails under genera such as *Ostrea* (sensu lato) or reassign them to other closely related families like Trochidae or Trochomorphidae.

Osteriidae snails play a role in marine ecosystems as part of the benthic community, contributing to nutrient cycling and serving as prey for various predators. Their ecological importance varies by species, but they are generally considered minor components of reef and seafloor habitats. Fossil records of Osteriidae are limited, but their presence in some Paleogene deposits suggests a long evolutionary history.