![]() Hoyle ( 1886), who described the subgenus Metasepia in 1885, did not concur with Rochebrune’s classification, stating that the defining characters were at best of subgeneric value. Rochebrune ( 1884) subsequently proposed ten genera based on cuttlebone characters. He also redescribed Sepiella based on the shell and soft parts, raising it to generic status (Steenstrup 1880). typicus as the type species based on the animal and the cuttlebone. Later, Steenstrup ( 1875: 468) erected Hemisepius with H. He coined the name Sepiella, then known only from cuttlebones (and not whole animal soft parts), for species with cuttlebones that were described as ‘oblong, posterior end expanded, produced, cartilaginous, not beaked, convex beneath’ (Gray 1849: 106). Gray ( 1849) partially adopted d’Orbigny’s classification and additionally included cuttlebone characters. He classified them into two groups based on the arrangement and relative sizes of suckers on the arms and tentacular clubs. In 1845, d’Orbigny listed 21 species, most of which are still valid. Lamarck ( 1799) limited the genus to include only those cephalopods with an internal calcareous shell. The study and naming of cuttlefishes according to modern taxonomy dates to Linnaeus ( 1758), with the genus Sepia first recognised to include all cephalopods without an external shell. Multiple processes have led to high levels of faunal biodiversity in the region (Halas and Winterbottom 2009). 2013), the Indo Pacific harbours their greatest diversity (Rosa et al. As is the case for many marine taxa (Hoeksema 2007 Sanciangco et al. 1998 Neige 2003) adults are demersal, mostly occurring in the neritic zone, although some species inhabit deeper waters. Juveniles (with a few notable exceptions) are primarily benthic following hatching and there is no paralarval stage (Young et al. 2014).Ĭuttlefish diversity can be partly explained by their biology and biogeography. This species-rich family is well defined as a discrete monophyletic taxonomic unit (Allcock et al. Where possible, each genus is diagnosed based on a combination of morphological and molecular characters.Ĭuttlefishes are found in temperate to tropical waters over continental shelves and slopes, from the western Pacific, the Indian Ocean and to the eastern Atlantic, as far north as the North Sea. angulata Roeleveld, 1972 we tentatively assign these two taxa to Spathidosepion pending future confirmation. Based on the morphological similarity between S. Sepia tuberculata Lamarck, 1798, the type species for the nominal genus Spathidosepion, was not included for the same reason. typicus Steenstrup, 1875, was not included in our molecular analysis as tissue samples could not be obtained. Hemisepius Steenstrup, 1875, also monotypic, is recognised as valid based on a unique synapomorphy: the presence of a fleshy ridge on each side of the antero-ventral mantle that bears a longitudinal row of black pores, however, H. Sepia trygonina (Rochebrune, 1884) and Sepia hieronis (Robson, 1924) are placed in new monotypic genera Erythalassa gen. The subgenus Digitosepia Lipiński, 2020 is well supported and is herein elevated to generic status. Sepia Linnaeus, 1758 and Sepiella Gray, 1849 are retained, but Metasepia Hoyle, 1885 is placed in alternative combination with Ascarosepion. Based on a comprehensive analysis of molecular sequence data, the Sepiidae genera Acanthosepion Rochebrune, 1884 Ascarosepion Rochebrune, 1884 Aurosepina Jothinayagam, 1987 Decorisepia Iredale, 1926 Doratosepion Rochebrune, 1884 Rhombosepion Rochebrune, 1884 and Spathidosepion Rochebrune, 1884 are here re-instated and formally recognised as valid.
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