Cryptogemma, DALL, 1918

Zaharias, Paul, Kantor, Yuri I., Fedosov, Alexander E., Criscione, Francesco, Hallan, Anders, Kano, Yasunori, Bardin, Jérémie & Puillandre, Nicolas, 2020, Just the once will not hurt: DNA suggests species lumping over two oceans in deep-sea snails (Cryptogemma), Zoological Journal of the Linnean Society 190, pp. 532-557 : 539

GENUS CRYPTOGEMMA DALL, 1918

Type species: Gemmula benthima Dall, 1908 ( OD) .

Ptychosyrinx Thiele, 1925 (type species: Pleurotoma bisinuata Martens, 1901 – OD).

Bathybermudia Haas, 1949 (type species: Bathybermudia carynae Haas, 1949 – OD).

† Pinguigemmula McNeil, 1960 (type species † Pinguigemmula okinavensis McNeil, 1960 – OD).

Included species: Cryptogemma aethiopica (Thiele, 1925) ; C. periscelida (Dall, 1889) ; C. phymatias (Watson, 1886) ; C. powelli ; C. praesignis (Smith, 1895); C. tessellata ( Powell, 1964) ; C. timorensis ( Tesch, 1915) ; C. unilineata ( Powell, 1964) .

Remarks: According to WoRMS (checked http://www. marinespecies.org/, July2019), Cryptogemma comprises 11 species and has never been revised. A consultation of available type photographs and published images on Cryptogemma species indicated that all 11 species, except the type species C. benthima and C. phymatias , the senior synonym of C. benthima , should be excluded from the genus, because the majority of them lack key characters, such as the narrow fusiform shell and the well-marked peripheral anal sinus. Moreover, studied samples from Japan, most certainly corresponding to Cryptogemma corneus (Okutani, 1966) as pictured by Hasegawa (2009: figs 335–338), showed closer affinity to other conoidean families (e.g. Horaiclavidae ) than to the Turridae , based on both the sequence of the barcode fragment of COI and the radular morphology (results not shown). The eight species of Cryptogemma listed herein have wide distributions, most of them covering the whole Indo-Pacific tropical region, and are not found at depths shallower than 200 m.

The protoconch consists of four to 5.25 whorls. The shell shape of the teleoconch combined with size is an important factor to distinguish species (see Results section), despite high intraspecific variability.The widest range of variability is observed in shell proportions, with shells with a wide last whorl and long siphonal canal being at one extreme of the range and more elongated shells with short siphonal canal at the other.