''Semicassis'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of medium-sized predatory sea snails,

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

gastropod molluscs in the subfamily

Cassinae The Cassidae are a taxonomic family of medium-sized, large, and sometimes very large sea snails commonly called helmet snails or bonnet snails. These are marine gastropod mollusks in the superfamily Tonnoidea and the clade Littorinimorpha.Gof ...

within the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Cassidae The Cassidae are a taxonomic family of medium-sized, large, and sometimes very large sea snails commonly called helmet snails or bonnet snails. These are marine gastropod mollusks in the superfamily Tonnoidea and the clade Littorinimorpha.Gofas ...

, the helmet snails and bonnet snails.WoRMS : Semicassis; accessed: 30 July 2020
/ref>

Species

According to the

World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive list of names of marine organisms. Content The content of the registry is edited and maintained by scientific speciali ...

(WoRMS), the following species with valid names are included within the genus ''Semicassis'': *''

Semicassis adcocki ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' (Sowerby III, 1896) *''

Semicassis angasi ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species ( ...

'' (Iredale, 1927) *''

Semicassis bisulcata ''Semicassis bisulcata'', common name: the Japanese bonnet, is a species of large sea snail, a marine gastropod mollusk in the family Cassidae, the helmet snails and bonnet snails. Description The size of an adult shell varies between 25&nb ...

'' (Schubert & Wagner, 1829) *'' Semicassis bondarevi'' Mühlhäusser & Parth, 1993 *'' Semicassis bulla'' Habe, 1961 *''

Semicassis canaliculata ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (Wo ...

'' (Bruguière, 1792) * ''

Semicassis cancellata ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species ( ...

'' (Lamarck, 1803) *''

Semicassis centiquadrata ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species ( ...

'' (Valenciennes, 1832) *''

Semicassis craticulata ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species ( ...

'' (Euthyme, 1885) * ''

Semicassis decipiens ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' (Kilburn, 1980) * ''

Semicassis dorae ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species ( ...

'' (Kreipl & Mühlhäusser, 1996) * '' Semicassis dougthorni'' Dekkers, 2013 *''

Semicassis faurotis ''Phalium faurotis'' is a species of large sea snail, a marine gastropod mollusk in the family Cassidae, the helmet snails and bonnet snails. MolluscaBase eds. (2021). MolluscaBase. Semicassis faurotis (Jousseaume, 1888). Accessed through: Wo ...

'' (Jousseaume, 1888) * ''

Semicassis fernandesi ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' (Kilburn, 1975) * † ''

Semicassis fibrata ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species ( ...

'' (P. Marshall & Murdoch, 1920) *''

Semicassis glabrata ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species ( ...

'' (Dunker, 1852) *''

Semicassis granulata The Scotch bonnet (''Semicassis granulata'') is a medium-sized to large species of sea snail, a marine gastropod mollusk in the subfamily Cassinae, the helmet shells and bonnet shells. The common name "Scotch bonnet" alludes to the general ou ...

'' (Born, 1778) - synonym: ''Phalium granulatum'' (Born, 1778) * † ''

Semicassis grateloupi ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (W ...

'' (Deshayes, 1853) *''

Semicassis inornata ''Semicassis inornata'' is a species of large sea snail, a marine gastropod mollusc in the family Cassidae The Cassidae are a taxonomic family of medium-sized, large, and sometimes very large sea snails commonly called helmet snails or bon ...

'' (Pilsbry, 1895) * † ''

Semicassis kaawaensis ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' (Bartrum & Powell, 1928) *'' Semicassis labiata'' (Perry, 1811) * † ''

Semicassis laevigata ''Semicassis'' is a genus of medium-sized predatory sea snails, marine (ocean), marine gastropod molluscs in the subfamily Cassinae within the family (biology), family Cassidae, the helmet snails and bonnet snails. Species According to the World ...

'' (Defrance, 1817) * †''

Semicassis lilliei ''Semicassis'' is a genus of medium-sized predatory sea snails, marine (ocean), marine gastropod molluscs in the subfamily Cassinae within the family (biology), family Cassidae, the helmet snails and bonnet snails. Species According to the World ...

'' (C. A. Fleming, 1943) * † ''

Semicassis marwicki ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' (C. A. Fleming, 1943) *''

Semicassis microstoma ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (Wo ...

'' (Martens, 1903) * † '' Semicassis neumayri'' (Hoernes, 1875) *''

Semicassis paucirugis ''Semicassis'' is a genus of medium-sized predatory sea snails, marine (ocean), marine gastropod molluscs in the subfamily Cassinae within the family (biology), family Cassidae, the helmet snails and bonnet snails. Species According to the World ...

'' (Menke, 1843) *''

Semicassis pyrum ''Semicassis pyrum'', common name the "pear bonnet" or "common helmet", is a species of large sea snail, a marine gastropod mollusc in the family Cassidae The Cassidae are a taxonomic family of medium-sized, large, and sometimes very large ...

'' (Lamarck, 1822) *''

Semicassis royana ''Semicassis royana'' is a species of medium-sized predation, predatory sea snail, a marine (ocean), marine gastropoda, gastropod mollusca, mollusc in the family Cassidae, the helmet shells and their allies. References

* Arthur William Bade ...

'' (Iredale, 1914) *''

Semicassis saburon ''Semicassis saburon'' is a species of large sea snail, a marine gastropod mollusc in the family Cassidae The Cassidae are a taxonomic family of medium-sized, large, and sometimes very large sea snails commonly called helmet snails or bonn ...

'' (Bruguière, 1792) *'' Semicassis semigranosa'' (Lamarck, 1822) *''

Semicassis sinuosa ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' (Verco, 1904) * † ''

Semicassis skinneri ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' (Marwick, 1928) *''

Semicassis sophia ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' (Brazier, 1872) * † ''

Semicassis subsulcosa ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (Wo ...

'' (Hoernes & Auinger, 1884) * † ''

Semicassis szilviae ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' Kovács & Vicián, 2018 *''

Semicassis thachi ''Semicassis thachi'' is a species of large sea snail, a marine (ocean), marine gastropod mollusc in the family (biology), family Cassidae, the helmet snails and bonnet snails. Description Distribution References External links

Cass ...

'' Kreipl, Alf & Eggeling, 2006 *''

Semicassis thomsoni ''Semicassis thomsoni'' is a species of large predatory sea snail, a marine gastropod mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). ...

'' (Brazier, 1875) *'' Semicassis umbilicata'' (Pease, 1861) * '' Semicassis undulata'' (Gmelin, 1791) *''

Semicassis westralis ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' Kreipl, 1997 *''

Semicassis whitworthi ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (Wo ...

'' (Abbott, 1968) * ''

Semicassis zeylanica ''Semicassis'' is a genus of medium-sized predatory sea snails, marine gastropod molluscs in the subfamily Cassinae within the family Cassidae, the helmet snails and bonnet snails. Species According to the World Register of Marine Species (WoRMS ...

'' (Lamarck, 1822) ;Species brought into synonymy: * ''Semicassis cicatricosa'' (Gmelin, 1791): synonym of ''

'' (Born, 1778) * ''Semicassis diuturna'' Iredale, 1927: synonym of ''Semicassis bisulcata'' (Schubert & J. A. Wagner, 1829) * ''Semicassis japonica'' (Reeve, 1848): synonym of ''Semicassis bisulcata'' (Schubert & J. A. Wagner, 1829) * ''Semicassis miolaevigata'' Sacco, 1890: synonym of ''Semicassis saburon'' (Bruguière, 1792) * ''Semicassis obscura'' Habe, 1961: synonym of ''Semicassis bulla'' Habe, 1961 * ''Semicassis pauciruge'': synonym of ''Semicassis paucirugis'' (Menke, 1843) * ''Semicassis persimilis'' Kira, 1955: synonym of ''Semicassis bisulcata'' (Schubert & J. A. Wagner, 1829) * ''Semicassis pila'' (Reeve, 1848): synonym of ''Semicassis bisulcata'' (Schubert & J. A. Wagner, 1829) * ''Semicassis salmonea'' Beu, Bouchet & Tröndlé, 2012: synonym of '' Semicassis bulla'' Habe, 1961 Cassidae - Semicassis rondoletii

Extinct Species

Extinct species within this genus include:Fossilworks
/ref> *''Semicassis aldrichi'' Dall 1890 † *''Semicassis angasi'' Iredale 1927 † *''Semicassis deneseplicata'' Martin 1916 † *''Semicassis harpaeformis'' Lamarck 1803 † *''Semicassis labiata'' Perry 1811 † *''Semicassis monilifera'' Sowerby 1846 † *''Semicassis oligocalantica'' Vredenburg 1925 † *''Semicassis ovulum'' Ortmann 1900 † *''Semicassis pyshtensis'' Addicott 1976 † *''Semicassis reclusa'' Guppy 1873 † Fossils of species within this genus have been found all over the world in sediments from

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

to Quaternary (age range: 37.2 to 0.0 million years ago).

References

* Powell A. W. B. (1979). William Collins Publishers Ltd, Auckland . Cassidae Gastropod genera Extant Eocene first appearances {{Cassidae-stub