Gemmula
Gemmula, common name the gem turrids, is a genus of sea snails, marine gastropod mollusks in the family Turridae, the turrids.
These snails have been recorded as fossils from the Paleocene to the Quaternary. Fossils have been found all over the world.
This genus is still regarded as paraphyletic and was revised in 2024. A high number of undescribed species are estimated to belong to Gemmula. Since independent “Gemmula-like” lineages are distributed all over the turrid tree, a revision of Gemmula would entail again a complete revision of the family Turridae.
This revision has been made in 2024 as part of the generic revision of the Recent Turridae. Gemmula has been split up in 10 new genera.
They are venomous with disulfide-rich polypeptides in their venom ducts.
These bioactive peptides are likely to become a resource for novel pharmacologically active compounds
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 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, 1843The 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 of fine arcuate longitudinal riblets.
As expected from venomous species, these species have a toxoglosson radula 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 alwyni Kilburn, 2005- † Gemmula antedenticulata Lozouet, 2017
- † Gemmula bearrizensis Pacaud, 2021
- † Gemmula bimarginata
- † Gemmula birmanica Vredenburg, 1921
- † Gemmula brevirostris Lozouet, 2017Gemmula chinoi Stahlschmidt, Poppe & Tagaro, 2018
- † Gemmula clifdenensis Powell, 1942 Gemmula closterion Sysoev, 1997Gemmula concinna Gemmula contrasta Stahlschmidt, Poppe & Tagaro, 2018
- † Gemmula denticula
- † Gemmula disjuncta Laws, 1936 Gemmula ducalis
- † Gemmula duplex Gemmula flata Baoquan Li & Xinzheng Li, 2008
- † Gemmula funiculosa Lozouet, 2017
- † Gemmula garviei Tracey & Craig, 2019 Gemmula grandigyrata Baoquan Li & Xinzheng Li, 2008Gemmula granosus Gemmula hindsiana Berry, 1958Gemmula husamaru Gemmula interpolata Powell, 1967
- † Gemmula kaiparaensis Gemmula kieneri
- † Gemmula lawsi Powell, 1942
- † Gemmula longwoodensis Powell, 1942 Gemmula lordhoweensis Kantor & Sysoev, 1991Gemmula lululimi Olivera, 1999
- † Gemmula machapoorensis C.J. Maury, 1925
- † Gemmula margaritata Gemmula martini Gemmula mystica Simone, 2005
- † Gemmula obesa Lozouet, 2017 Gemmula oliverai Stahlschmidt, Poppe & Tagaro, 2018
- † Gemmula orba Marwick, 1931
- † Gemmula ornata
- † Gemmula osca Pacaud, 2021
- † Gemmula parkinsonii
- † Gemmula peraspera Marwick, 1931
- † Gemmula peyrerensis
- † Gemmula polita Gemmula pseudostupa Y.-P. Cheng & C.-Y. Lee, 2011
- † Gemmula reticulata Gemmula rotata
- † Gemmula samueli
- † Gemmula sculpturata Harzhauser, Raven & Landau, 2018 Gemmula sibogae Gemmula sibukoensis Powell, 1964Gemmula sikatunai Olivera, 2004Gemmula stupa Lee, 2001
- † Gemmula tuckeri Tracey & Craig, 2019 Gemmula vagata
- † Gemmula waihaoensis Finlay, 1924 Gemmula webberae Kilburn, 1975