''Semicassis'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of medium-sized predatory

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

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 The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

s 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.Go ...

within the

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

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 specialist ...

(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 (W ...

'' (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 (W ...

'' (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&n ...

'' (Schubert & Wagner, 1829) *''

Semicassis bondarevi ''Semicassis bondarevi'' is a species of marine gastropod in the family Cassidae. Distribution This species occurs on the submarine Mascarene Plateau (primarily the Saya de Malha Bank) and southern Mozambique.; also off Papua New Guinea. Refer ...

'' Mühlhäusser & Parth, 1993 *''

Semicassis bulla ''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 ...

'' 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 (W ...

'' (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 (W ...

'' (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 (W ...

'' (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 (W ...

'' (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 (W ...

'' (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 (W ...

'' (Kreipl & Mühlhäusser, 1996) * ''

Semicassis dougthorni ''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 ...

'' Dekkers, 2013 *''

Semicassis faurotis ''Phalium faurotis'' is a species of large sea snail, a marine gastropod mollusk 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 bonne ...

'' (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 (W ...

'' (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 (W ...

'' (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 (W ...

'' (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 ...

'' (Born, 1778) - synonym: ''Phalium granulatum'' (Born, 1778) * † '' Semicassis grateloupi'' (Deshayes, 1853) *''

Semicassis inornata ''Semicassis inornata'' 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 This marine species occurs off Japan. ...

'' (Pilsbry, 1895) * † '' Semicassis kaawaensis'' (Bartrum & Powell, 1928) *''

Semicassis labiata ''Semicassis labiata'' (formerly also known as ''Phalium labiatum'') is a species of large predatory sea snail, a marine gastropod mollusc. This species is in the subfamily Cassinae, the "helmet shells" and "bonnet shells", which feed on sea urch ...

'' (Perry, 1811) * † '' Semicassis laevigata'' (Defrance, 1817) * †''

Semicassis lilliei ''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 ...

'' (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 ...

'' (Martens, 1903) * † ''

Semicassis neumayri ''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 ...

'' (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 lar ...

'' (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 (ocean), marine gastropod mollusc in the family (biology), family Cassidae, the helmet snails and bonnet snails. Description The shell of ''Semicassis saburon'' can reach a size of ...

'' (Bruguière, 1792) *''

Semicassis semigranosa ''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 ...

'' (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'' (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 (WoRMS ...

'' (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'' (Brazier, 1875) *''

Semicassis umbilicata ''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 ...

'' (Pease, 1861) * ''

Semicassis undulata ''Semicassis undulata'' is a Mediterranean species of medium-sized sea snail, a marine gastropod mollusc in the subfamily Cassinae, the helmet snails and bonnet snails. Taxonomy This taxon was previously sometimes referred to at subspecies ...

'' (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 (W ...

'' (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 ''

'' 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 (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ...

(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