Alvania zylensis Gofas and Warén, 1982

Gofas, Serge, 2007, Rissoidae (Mollusca: Gastropoda) from northeast Atlantic seamounts, Journal of Natural History 41 (13 - 16), pp. 779-885 : 791

Alvania zylensis Gofas and Warén, 1982

( Figure 5C–E )

Material examined Gorringe— Seamount 1 sta. DW05, 15 sh. (1.76×1.12 to 2.18× 1.34 mm; DW06, 19 sh.

(1.70×1.16 to 2.22× 1.50 mm); DW08, 6 sh. (1.84×1.28 to 2.08× 1.38 mm); DE09, 17 sh. (1.80×1.16 to 2.60× 1.30 mm); CP12, 1 sh.; DW16, 15 sh. (1.82×1.26 to 2.44× 1.46 mm); CP20, 1 spm. (2.25× 1.40 mm) and 3 sh. (2.40× 1.56 mm). Ampère— Seamount 1 sta. DW92, 7 sh. (1.62×1.06 to 2.58× 1.44 mm); DE98, 1 sh. (2.48× 1.68 mm); Victor Hensen VH 97 sta. 296, 3 sh. (1.90×1.16 to 2.16× 1.24 mm); sta. 298, 2 sh. (1.94×1.18, 2.50× 1.32 mm) and 3 jv. sh.

Remarks

This species has a multispiral protoconch although there is some variation in its number of whorls. It is uncommon on the Ibero-Moroccan shelf, where it is restricted to circalittoral hard bottoms. On Gorringe and Ampère, it is not so rare possibly due to availability of its preferred habitat. It was also recorded from Gorringe by Ávila and Malaquias (2003).

Figures

Figure 5. Alvania species from Lusitanian seamounts, shared with the mainland shelf. (A) A. cancellata (da Costa, 1778), shell from Gorringe seamount, DW33 (55–70 m), actual size 4.90 mm; (B) A. cancellata, protoconch of a shell from Ampère seamount, DE98 (300–325 m); (C) A. zylensis Gofas and Warén, 1982 from Gorringe seamount, CP20 (305–320 m), actual size 2.25 mm; (D) protoconch of the same specimen; (E) A. zylensis from Ampère seamount, DW92 (117–129 m), actual size 2.00 mm; (F) A. punctura (Montagu, 1803), protoconch of a shell from Gorringe seamount, CP 20; (G) Alvania vermaasi van Aartsen, 1975, protoconch of a shell from Gorringe seamount, DW08 (470–485 m). Scale bars: 100 Mm.