Habitat and feeding habits
The snails in this genus occur mostly in deeper tropical waters at depths between 50 and 500m. Because of these deep habitats, little is known about their feeding habits.Taxonomy
The ''Gemmula'' clade is more closely related to the clades ''Xenuroturris'', ''Turris'' and ''Lophiotoma'' than to the other clades in the former subfamily Turrinae.Description
The fusiform shell resembles ''Drillia,'' but with a thin and simple outer Lip (gastropod), lip without an anterior sulcus, and the inner lip usually simple, hardly callous. The protoconch is polygyrate and axially costate. There are three or four embryonal whorls, the two upper ones smooth, upright, the others longitudinally ribbed. The sculpture is most emphasized in a spiral direction, often with a prominent beaded keel at or in front of the anal fasciole.The rather long siphonal canal is narrow and tapering, sometimes curved. The sinus is straight, more or less narrow and long, terminating in a nodulous peripheral keel that is gemmate throughout. Type species : ''Pleurotoma gemmata'' Hinds, 1843 The bead-row of the fasciole readily distinguishes this genus from related forms. Between the smooth protoconch and the adult whorls two or three whorls intervene with descrepant Sculpture (mollusc), sculpture of fine arcuate longitudinal riblets. As expected from venomous species, these species have a toxoglosson radula (formula 1 + 0 +1 + 0 + 1) with a central tooth that characterizes this genus.Species
The genus ''Gemmula'' is the largest genus in the former subfamily Turrinae. Species within the genus ''Gemmula'' include: * ''Gemmula albina'' (Lamarck, 1822) * ''Gemmula alwyni'' Kilburn, 2005 * ''Gemmula amabilis'' (Weinkauff, 1875) * ''Gemmula ambara'' Olivera et al., 2008 * † ''Gemmula antedenticulata'' Lozouet, 2017 * † ''Gemmula bearrizensis'' Pacaud, 2021 * † ''Gemmula bimarginata'' (Suter, 1917) * † ''Gemmula birmanica'' Vredenburg, 1921 * † ''Gemmula brevirostris'' Lozouet, 2017 * ''Gemmula championi'' Kilburn, 1983 * ''Gemmula chinoi'' Stahlschmidt, Poppe & Tagaro, 2018 * † ''Gemmula clifdenensis'' Powell, 1942 * ''Gemmula closterion'' Sysoev, 1997 * ''Gemmula concinna'' (Dunker, 1871) * ''Gemmula congener'' (Smith E. A., 1894) * ''Gemmula contrasta'' Stahlschmidt, Poppe & Tagaro, 2018 * ''Gemmula cosmoi'' (Sykes, 1930) * ''Gemmula damperierana'' Powell, 1964 * † ''Gemmula denticula'' (Basterot, 1825) * ''Gemmula diomedea'' Powell, 1964 * † ''Gemmula disjuncta'' Laws, 1936 * ''Gemmula ducalis'' (Thiele, 1925) * † ''Gemmula duplex'' (Suter, 1917) * ''Gemmula fenestrata'' Kosuge, 1990 * ''Gemmula flata'' Baoquan Li & Xinzheng Li, 2008 * † ''Gemmula funiculosa'' Lozouet, 2017 * † ''Gemmula garviei'' Tracey & Craig, 2019 * ''Gemmula gemmulina'' (Martens, 1902) * ''Gemmula gilchristi'' (Sowerby III, 1902) * ''Gemmula graeffei'' (Weinkauff, 1875) * ''Gemmula grandigyrata'' Baoquan Li & Xinzheng Li, 2008 * ''Gemmula granosus'' (Helbling, 1779) * ''Gemmula hastula'' (Reeve, 1843) * ''Gemmula hawleyi'' (Iredale, 1931) * ''Gemmula hindsiana'' Berry, 1958 * ''Gemmula hombroni'' Hedley, 1922 * ''Gemmula husamaru'' (Nomura, 1940) * ''Gemmula interpolata'' Powell, 1967 * † ''Gemmula kaiparaensis'' (P. Marshall, 1918) * ''Gemmula kieneri'' (Doumet, 1840) * † ''Gemmula lawsi'' Powell, 1942 * ''Gemmula lisajoni'' Olivera, 1999 * † ''Gemmula longwoodensis'' Powell, 1942 * ''Gemmula lordhoweensis'' Kantor & Sysoev, 1991 * ''Gemmula lululimi'' Olivera, 1999 * † ''Gemmula machapoorensis'' C.J. Maury, 1925 * † ''Gemmula margaritata'' (P. Marshall, 1919) * ''Gemmula martini'' (Tesch, 1915) * ''Gemmula monilifera'' (Pease, 1860) * ''Gemmula murrayi'' Powell, 1964 * ''Gemmula mystica'' Simone, 2005 * † ''Gemmula obesa'' Lozouet, 2017 * ''Gemmula oliverai'' Stahlschmidt, Poppe & Tagaro, 2018 * † ''Gemmula orba'' Marwick, 1931 * † ''Gemmula ornata'' (P. Marshall, 1918) * † ''Gemmula osca'' Pacaud, 2021 * † ''Gemmula parkinsonii'' (Sandberger, 1860) * † ''Gemmula peraspera'' Marwick, 1931 * † ''Gemmula peyrerensis'' (Peyrot, 1931) * † ''Gemmula polita'' (P. Marshall, 1919) * ''Gemmula pseudogranosa'' (Nomura, 1940) * ''Gemmula pseudomonilifera'' Powell, 1967 * ''Gemmula pseudostupa'' Y.-P. Cheng & C.-Y. Lee, 2011 * ''Gemmula rarimaculata'' Kuroda, Habe & Oyama, 1971 * † ''Gemmula reticulata'' (P. Marshall, 1919) * ''Gemmula rosario'' Shikama, 1977 * ''Gemmula rotata'' (Brocchi, 1814) * † ''Gemmula samueli'' (Tenison Woods, 1879) * † ''Gemmula sculpturata'' Harzhauser, Raven & Landau, 2018 * ''Gemmula sibogae'' (Mattheus Marinus Schepman, Schepman, 1913) * ''Gemmula sibukoensis'' Powell, 1964 * ''Gemmula sikatunai'' Olivera, 2004 * ''Gemmula sogodensis'' Olivera, 2004 * ''Gemmula speciosa'' (Reeve, 1842) * ''Gemmula stupa'' Lee, 2001 * ''Gemmula subfenestrata'' Kosuge, 1990 * † ''Gemmula tuckeri'' Tracey & Craig, 2019 * ''Gemmula vagata'' (Smith E. A., 1895) * † ''Gemmula waihaoensis'' Finlay, 1924 * ''Gemmula webberae'' Kilburn, 1975 * ''Gemmula westaustralis'' Kosuge, 1990 ;Species brought into synonymy: * ''Gemmula aethiopica'' (Thiele, 1925): synonym of ''Cryptogemma aethiopica'' (Thiele, 1925) * ''Gemmula bisinuata'' (Martens, 1901): synonym of ''Cryptogemma praesignis'' (E. A. Smith, 1895) * ''Gemmula luzonica'' (Powell, 1964): synonym of ''Cryptogemma aethiopica'' (Thiele, 1925) * ''Gemmula microscelida'' (Dall, 1895): synonym of ''Cryptogemma praesignis'' (E. A. Smith, 1895) * ''Gemmula periscelida'' (Dall, 1889): synonym of ''Cryptogemma periscelida'' (Dall, 1889) * ''Gemmula praesignis'' (Smith E. A., 1895): synonym of ''Cryptogemma praesignis'' (E. A. Smith, 1895) * ''Gemmula rotatilis'' (Martens, 1902): synonym of ''Cryptogemma praesignis'' (E. A. Smith, 1895) * ''Gemmula teschi'' (Powell, 1964): synonym of ''Cryptogemma timorensis'' (Tesch, 1915) * ''Gemmula tessellata'' Powell, 1967: synonym of ''Cryptogemma tessellata'' (Powell, 1967) * ''Gemmula thielei'' Finlay H. J., 1930: synonym of ''Cryptogemma aethiopica'' (Thiele, 1925) * ''Gemmula truncata'' (Schepman, 1913): synonym of ''Cryptogemma phymatias'' (R. B. Watson, 1886) * ''Gemmula unedo'' (Kiener, 1840): synonym of ''Unedogemmula unedo'' (Kiener, 1839) * ''Gemmula unilineata'' Powell, 1967: synonym of ''Cryptogemma unilineata'' (Powell, 1967) * ''Gemmula vicella'' Dall, 1908 accepted as ''Gymnobela vicella'' (Dall, 1908) (original combination)References
* Powell, A.W.B. 1964. ''The Family Turridae in the Indo-Pacific. Part 1. The Subfamily Turrinae''. Indo-Pacific Mollusca 1: 227-346 * Kilburn, R.N. (1983) ''Turridae (Mollusca: Gastropoda) of southern Africa and Mozambique. Part 1. Subfamily Turrinae''. Annals of the Natal Museum, 25, 549–585.External links