Cylichnium oliviforme (Watson, 1883)

Fig. 30H‒J

Utriculus oliviformis Watson, 1883: 332.

Utriculus sp. – Watson 1886: 648, pl. 48 fig. 6.

Utriculus oliviformis – Dautzenberg & Fischer 1896: 400.

Cylichnium oliviforme (Watson, 1883) – Fechter 1979: 37–38.

Material examined

GALICIA BANK • 7 sh; 42°56.77′ N, 11°58.53′ W; 1631 m; 2 Aug. 2011; BANGAL 0711 V5; MNCN • 6 sh; 42°41.87′ N, 11°26.71′ W; 1720 m; 8 Aug. 2011; BANGAL 0711 V10; MNCN .

Remarks

This species was described tentatively by Watson (1883) and later retracted by Watson (1886) on the grounds of poor condition of the material examined, originating from off the Azores in 1000 fathoms (1850 m). The species was again found off the Azores by Dautzenberg & Fischer (1896) and confirmed as valid. It was later reported from off the NW Iberian Peninsula by Fechter (1979) and transferred to the genus Cylichnium Dall, 1908. The size given 0.32 inches (8.1 mm) and the depth of the type locality are in good agreement with our material. Bouchet (1975) reported Cylichnium africanum (Locard, 1897) from R/V “ Thalassa ” stn X 336 in southern Bay of Biscay (44°11′ N, 05°10′ W, 1850‒2050 m). He considered it distinct from Cylichnium oliviforme because, in his words, the latter is more distinctly flattened below the suture and has a finely reticulated sculpture in the upper part of the last whorl. Nevertheless, according to these characters we consider the shell figured by Bouchet (1975: pl. 4, c) as conspecific with our material. Conversely Locard (1897: pl. 2 figs 15‒19) illustrated, to represent his Aceras africana, a shell in which the last whorl almost completely covers the spire whereas both the type of C. oliviforme and our specimens have a descending last whorl. Therefore, we follow Fechter (1979) in using the name C. oliviforme for the Iberian species.