Turris faleiroi Kilburn, 1998

Kilburn, Richard N., Fedosov, Alexander E. & Olivera, Baldomero M., 2012, Revision of the genus Turris Batsch, 1789 (Gastropoda: Conoidea: Turridae) with the description of six new species, Zootaxa 3244 (1), pp. 1-58 : 24-25

Turris faleiroi Kilburn, 1998

Plate 13 , figs A–D

Turris faleiroi Kilburn, 1998: 159 , figs 8–9. Type loc.: off Algoa Bay, 100 m.

DESCRIPTION (modified after Kilburn 1998): Spire very high and base relatively short (a/l 0.34–0.36, b/l 0.30–0.31), spire orthoconoid with flattened whorls and shallow suture. Anal sinus shallow, asymmetrically and openly U-shaped.

Subsutural cord low, broad, rather ill-defined, bearing 3–4 spiral threads and microscopic spiral striae that are crenulated by axial sculpture. Sulcus shallow. Sinus cord thin, weakly and irregularly crenulated. Peripheral region of base with 3 slightly stronger, subequal spiral cords, interval between each pair with one intermediary ridge, flanked by several weaker threads; two of these cords visible on spire whorls (making a total of 4 cords per whorl, although the anteriormost may be hidden in suture). First teleoconch whorl with 4 thin lirae. Anterior end of last whorl with 20–25 lirae, those on rostrum close and even, those above stronger and more widely-spaced, their intervals with fine spiral striae. Fine, sharp, crispate collabral threads overall, crenulating the main spirals.

Pale brown, with lighter main spirals, bearing an occasional slightly darker reddish-brown fleck, protoconch light brown. Traces of a dull, pale brown periostracum retained interstitially.

Protoconch papillose, relatively large and blunt, of ca 1.8 whorls, smooth except for the last half-whorl which bears 8–16 arcuate axial ribs plus a spiral thread developing above suture near termination of protoconch; breadth of last whorl 1.60–1.75 mm.

Maximum length 43.5 mm.

DISTRIBUTION: Known only from the type locality, on the eastern fringe of the Agulhas Bank, South Africa.

TYPES: Holotype NMSA V6145 ; paratype 1 NMSA V6146 , juvenile; paratypes 2–3 in private hands .

REMARKS: This species has the southernmost distribution of all Turris spp , and is the only member of the genus to occur on the Agulhas Bank, south of South Africa, although it is evidently very localised in range. Its relatively large, papillose protoconch appears unique in the genus, but is characteristic of many Agulhas Bank molluscs. This probably reflects a Pleistocene origin, when during periods of maximum regression, those species with planktotrophic development, whose range had become progressively restricted to the edge of the present continental shelf, would have been threatened with extinction, as a consequence of their larvae being ultimately swept east into the South Indian Ocean by the reflexed Agulhas current, or ultimately by the West Wind drift.

The types, most of which were taken alive, were all collected in crayfish (rock lobster) pots, suggesting that the species is an opportunistic scavenger.

Figures

PLATE 13. Turris faleiroi Kilburn, 1998: A, B—Holotype, off Algoa Bay, South Africa, 100 m, NMSA V6145, 40.3 x 12.0 mm; C, D—off Algoa Bay, South Africa, 100 m, NMSA V2588; C—44.7 x 12.4 mm; D—59.7 x 12.7 mm.