Integrative taxonomy of enigmatic deep-sea true whelks in the sister-genera Enigmaticolus and Thermosipho (Gastropoda: Buccinidae) Author Chen, Chong Author Xu, Ting Author Fraussen, Koen Author Qiu, Jian-Wen text Zoological Journal of the Linnean Society 2021 2021-09-01 193 1 230 230 https://academic.oup.com/zoolinnean/article/193/1/230/6038916 journal article 10.1093/zoolinnean/zlaa134 0024-4082 GENUS THERMOSIPHO KANTOR ET AL. , 2013 Thermosipho Kantor et al. , 2013: 2188 . Type species: Eosipho auzendei Warén & Bouchet, 2001 , by original designation. Diagnosis (emended from Fraussen & Stahlschmidt, 2016 ): Shell medium to large, up to 70 mm in length, thin, dark brownish in coloration. Shell form broadly oviform with moderately wide, short spire that is usually corroded. Siphonal canal short and not well defined, open. Subsutural ramp lacking. Whorls inflated, completely smooth and lacking in significant sculpture except fine lines. Protoconch unknown. Periostracum thick, dark brown, adherent, with dense axial lamellae that are most evident on the subsutural zone. Operculum thick, corneous, brown, with terminal nucleus, semi-oval in shape and smaller than the aperture. Distribution: Hydrothermal vents in the East Pacific. Known from the East Pacific Rise between 17 and 23° N and the Pacific–Antarctic Ridge between 31 and 38°S ( Warén et al. , 2006 ). Remarks: See under Enigmaticolus . Included species: Thermosipho auzendei ( Warén & Bouchet, 2001 ) (original combination: Eosipho auzendei ).