The Gastropoda or gastropods, more commonly known as snails and slugs, are a large taxonomic class within the phylum Mollusca.
Snails are distinguished by an anatomical process known as torsion, where the visceral mass of the animal rotates 180° to one side during development, such that the anus is situated more or less above the head. This process is unrelated to the coiling of the shell, which is a separate phenomenon. Torsion is present in all gastropods, but the opisthobranch gastropods are secondarily de-torted to various degrees.
Gastropods typically have a well-defined head with two or four sensory tentacles with eyes, and a ventral foot, which gives them their name (Greek gaster, stomach, and poda, feet). The larval shell of a gastropod is called a protoconch.
The class Gastropoda contains a vast total of named species, second only to the insects in overall number. The fossil history of this class goes back to the early Cambrian.
Selection of related publications
- . Silurian cornulitids of Estonia (Baltica)
- . Predation on bellerophontiform molluscs in the Paleozoic
- . Paragastropoda, Tergomya and Gastropoda (Mollusca) from the Upper Ordovician Dalby Limestone, Sweden
- . Locality descriptions, the Siljan District
- . Bucania (Gastropoda) from the Ordovician of Estonia
- . Homeomorphic gastropods from the Silurian of Norway, Estonia and Bohemia
- . The platyceratacean gastropod Cyclonema (Cyclonema) hiiumaa Teichert, 1928 from the Llandovery (Silurian) of Estonia
- . Harjuan (Late Ordovician) new Bivalves and a new Gastropod from North Estonia
- . Atlas of Upper Ordovician and Silurian molluscs from the nort-western part of East-European platform.
- . Bivalvia and Gastropoda
- . Stratigraphy of the Viruan Series (Middle Ordovician) in Northern Estonia, I
- . Erisalu, päevik 5, Geoloogilise kaardistamise ekspeditsioon Nr.4, välipäevik
- . Beiträge zur Kenntnis der Kukruse-(C2-C3-)Stufe in Eesti. IV
- . Die gastropoden des baltischen Untersilurs
- . Lühike ülevaade Eesti geoloogiast. (Eozoiline ja paleozoiline ladekond)
- . Die Gastropoden des Baltischen Untersilurs
- . Die Leitfossilien. Ein Handbuch für den Unterricht und für das Bestimmen von Versteinerungen
- . On the Silurian Gastropoda and Pteropoda of Gotland
- . Die Fauna und Flora des Grunsandes von Moskwa
- . Untersuchungen über die Silurische Formation von Ehstland, Nord-Livland und Oesel