Onoba semicostata ( Montagu, 1803 )

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 : 36

Onoba semicostata ( Montagu, 1803)

( Fig. 21f )

Material examined. (2 empty shells in 2 samples): SPAIN • 1 sh 42° 30.391′ N, 009° 19.517′ W to 42° 29.428′ N, 009° 17.924′ W; 147–148 m; 17–28 SeP. 2004; VERTIDOS AG-EBS-150 • 1 sh; Polygon delimited by Points 44° 10.000′ N, 009° 00.000′ W /44° 10.000′ N, 008° 35.000′ W/44° 00.000′ N; 009° 00.000′ W/44° 07.000′ N; 008° 35.000′ W; 417–668 m ; SARRIDAL (2006–07) SARRI-3.

Remarks. It is a common sublittoral NE Atlantic, usually from the intertidal zone to about 100 m depth, and rarely deeper ( Fretter & Graham 1978; Nekhaev et al. 2014). Bouchet & Warén (1993) did not include it among the NE Atlantic bathyal species.

Only two empty shells and one fragment were found from two samples. One of the shells from 417–668 m was well preserved ( Fig. 21f ), which is surprising since O. semicostata is a shallow-water species.

Figures

FIGURE 21. Pusillina cf. radiata (Philippi, 1836). a–b Juvenile eroded shells (a: 1.6 mm; b: 1.7 mm) (SE:DRN-7); c Protoconch (VE:GA-AT-800); d Alvania cancellata (Da Costa, 1778) (0.96 mm) (VE:AG-EBS-150); e Crisilla semistriata (Montagu, 1808) (1.9 mm) (SE-08:EBS14); f Onoba semicostata (Montagu, 1803) (1.7 mm) (SA:SARRI-3); g Manzonia crassa (Kanmacher, 1798) (2.1 mm) (SE:DRN7).