Caenogastropods

Caenogastropoda is a major clade within the class Gastropoda, comprising a large and diverse group of snails that live in marine, freshwater, and some terrestrial environments. It includes many familiar forms and is supported by molecular data and distinctive developmental features that set it apart from other gastropod lineages.

Diversity and distribution: Most caenogastropods are marine, from shallow habitats to the deep sea, but freshwater and some terrestrial species exist. The group contains many species-rich lineages and a wide range of life histories.

Anatomy and life history: Members typically have a shell, often with a siphonal canal, and a prominent mantle cavity. They exhibit diverse feeding modes, from grazing to predation. Larval development is often free-swimming, though direct development occurs in some lineages.

Taxonomy and phylogeny: The clade includes several well-known lineages, notably Neogastropoda (many carnivorous sea snails) and Littorinimorpha (numerous marine and freshwater groups). Classification has evolved with new molecular data, but Caenogastropoda remains a core component of gastropod systematics.

Ecology and significance: Caenogastropods play key ecological roles as grazers and predators in aquatic systems. They are collected for shells, kept in aquaria, and some species have economic importance in fisheries and aquaculture. Conservation concerns affect several habitats.