Tonnidae

Tonnidae
A shell of Tonna tankervillii (Hanley, 1860)
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Caenogastropoda
clade Hypsogastropoda
clade Littorinimorpha
Superfamily: Tonnoidea
Family: Tonnidae
Suter, 1913

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 the shells are thin, they are also strong. There is no operculum. 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.[1]

Taxonomy

In 2005, these subfamilies were recognized in the taxonomy of Bouchet & Rocroi:

Bouchet & Rocroi (2005) listed Cassidae as a synonym of Tonnidae Suter, 1913 (1825), following Riedel (1995) in this. However, later Beu (2008: 272) separated the two families.[2] This is in agreement with the action of Thiele (1925) who placed Tonnidae and Cassidae under "Tonnacea", therefore acting as first reviser under ICZN article 24. In this respect, the World Register of Marine Species follows the opinion of Beu. [3]

Genera

Genera and species within the family Tonnidae include:

The subfamily Cassinae has been raised to the rank of family Cassidae

Genera brought into synonymy 

References

  1. Rehder, Harold A., 1981, National Audubon Society Field Guide to Shells, pg. 503
  2. Beu A. G. (2008). "Recent deep-water Cassidae of the world. A revision of Galeodea, Oocorys, Sconsia, Echinophoria and related taxa, with new genera and species (Mollusca, Gastropoda)". In: Héros V., Cowie R. H. & Bouchet P. (eds). "Tropical Deep-Sea Benthos 25". Mémoires du Muséum National d'Histoire Naturelle 196: 269-387. abstract in French.
  3. Gofas, S. (2011). Cassidae. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=22999 on 2011-02-23

External links

Wikimedia Commons has media related to Tonnidae.