Alvania wareni ( Templado & Rolán, 1986 )

Oliver, Joan Daniel, Gofas, Serge, Urgorri, Victoriano, Díaz-Agras, Guillermo & Templado, José, 2022, Rissoidae gastropods of the outer continental shelf and slope off Galicia (NW Spain), Zootaxa 5196 (1), pp. 1-45 : 15

Alvania wareni ( Templado & Rolán, 1986)

( Fig. 8 )

Material examined. (5 empty shells in the same sample): • 5 sh; 44° 09.896′N, 008° 39.581′W to 44° 10.129′N, 008° 39.494′W; 438–459 m; 15–24 Jul. 2008; A SELVA DRN-11 .

Remarks. This species was only known previously from two specimens found off Portugal, one the holotype (from PORCUPINE Expedition, at 1809 m depth) and the other from THALASSA expedition at 810 m ( Bouchet & Warén 1993). Therefore, the five shells found in one of the samples studied at about 450 m depth extend the knowledge on this rare species and expand its distribution area and bathymetric range. They are fusiform, up to 2.7 x 1.4 mm, with a high spire, whose general shape resembles some European species of Onoba ( Figs. 8a–b ). Sculpture of weak spiral cords and axial ribs of similar width somewhat narrower than their respective interspaces. Microsculpture of fine striae ( Fig. 8c ). Oval aperture with thin outer lip. Dome-shaped paucispiral protoconch ( Figs. 8d, g ) with fine equidistant spiral threads starting from the nucleus ( Fig. 8h ). Some details of its microsculpture are shown in Figure 8e–i .

Figures

FIGURE 8. Alvania wareni (Templado & Rolán, 1986) (SE: DRN-11). a Shell (2.5 mm); b Shell (2.7 mm); c Detail of the microsculpture of the teleoconch from b; d Lateral view of the protoconch; e–f Details of the microsculpture of the protoconch; g Apical view of another protoconch; h–i Detail of the microsculpture of the embryonic protoconch.