Turritelloidea

Turritelloidea is a superfamily of small to medium-sized sea snails, belonging to the clade Caenogastropoda within the class Gastropoda. These marine gastropods are characterized by their elongated, turreted shells, which often resemble a spiral staircase. The name "Turritelloidea" derives from the genus *Turritella*, one of the most well-known members of this group.

The shells of Turritelloidea are typically cylindrical or conical, with a series of whorls that gradually increase in size. They often exhibit a smooth or ribbed surface, depending on the species, and may be colored in shades of white, brown, or gray. Some species possess a siphonal canal, an extension of the shell that aids in respiration and feeding. The operculum, a hard structure that seals the shell when retracted, is usually present but varies in form among different taxa.

Turritelloidea are primarily found in shallow marine environments, including sandy or muddy substrates, where they burrow into the sediment. They are distributed worldwide, with the highest diversity observed in tropical and subtropical regions. These snails are suspension feeders, using a specialized feeding apparatus to filter plankton and organic particles from the water.

Fossil records indicate that Turritelloidea have existed since the Jurassic period, with many extinct lineages contributing to the evolutionary history of the group. Modern representatives include genera such as *Turritella*, *Terebellum*, and *Cancellaria*, each exhibiting unique adaptations to their ecological niches.

While Turritelloidea are not typically considered economically significant, they play important roles in marine ecosystems as both prey and predators. Their shells are occasionally collected by fossil enthusiasts and malacologists for study and display. The superfamily serves as a valuable subject in evolutionary and ecological research due to its diverse morphology and widespread distribution.