Tonnidae


The Tonnidae are a family of medium-sized to very large sea snails, known as the tun shells. These are marine gastropod molluscs in the clade Littorinimorpha. The name tun refers to the snails' shell shape, which resembles wine casks known as "tuns". While thin, the shells are also strong and lack opercula. They are found in all tropical seas, where they inhabit sandy areas. During the day, they bury themselves in the substrate, emerging at night to feed on echinoderms, crustaceans, and bivalves. Some larger species also capture fish, using their expandable probosces to swallow them whole. Females lay rows of eggs that become free-swimming larvae for several months before settling to the bottom.

Taxonomy

In 2005, these subfamilies were recognized in the [Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005)|taxonomy of Bouchet & Rocroi]:
Bouchet & Rocroi listed Cassidae as a synonym of Tonnidae Suter, 1913, following Riedel in this. However, later Beu separated the two families. This is in agreement with the action of Thiele (zoologist)|Thiele] who placed Tonnidae and Cassidae under "Tonnacea", therefore acting as first reviser under International Code of [Zoological Nomenclature|ICZN] article 24. In this respect, the World [Register of Marine Species] follows the opinion of Beu.

Genera

Genera and species within the family Tonnidae include:
The subfamily Cassinae has been raised to the rank of family CassidaeEudolium Dall, 1889Malea Vallenciennes, 1832Tonna Brunnich, 1771
;Genera brought into synonymy :Cadium Link, 1807 : synonym of Tonna Brunnich, 1771Cadus Röding, 1798 : synonym of Tonna Brunnich, 1771Cassidaria Link, 1807 : synonym of Eudolium Dall, 1889Doliopsis di Monterosato, 1872 : synonym of Eudolium Dall, 1889Foratidolium Rovereto, 1899: synonym of Tonna Brünnich, 1771Macgillivrayia Forbes, 1852 : synonym of Tonna Brünnich, 1771Dolium Lamarck, 1801: synonym of Tonna Brunnich, 1771Parvitonna Iredale, 1931: synonym of Tonna Brunnich, 1771Perdix Montfort, 1810: synonym of Tonna Brunnich, 1771Quimalea Iredale, 1929: synonym of Malea Valenciennes, 1832