Jujubinus swinneni Mariottini, Oliverio & Smriglio sp. nov.

urn:lsid:zoobank.org:act: 12A01241-73C7-4798-B44D-4BF13D21A1C5

SSH V – Fig. 6P–R

Jujubinus gravinae sensu Rolán & Swinnen 2009: figs 33–39, and sensu Hernández et al. 2011: 428, figs 14a–e (not Dautzenberg, 1881)

Diagnosis

Shell of medium size for the genus, solid, 5–6 spaced spiral cords, elevated, granulose, wide interspaces like the cords, with strong prosocline lamellae, peripheral cord very evident, high height/width ratio.

Etymology

The species is named after our friend Frank Swinnen, for his help in finding specimens of Jujubinus.

Type material

Holotype CANARY ISLANDS • lv (height 6.5 mm, width 4.8 mm); Gran Canaria, Arinaga; 27°51′21.24″ N, 15°23′46.61″ W; 25 Jan. 2016; low tide, amidst weeds, on rocky plateau with small stones; F. Swinnen and Martin Coysman leg.; used for DNA sequencing; MNHN-IM-2000-40309 (ex BAU2944.1).

Paratypes CANARY ISLANDS • 1 dd; same data as for holotype; MNHN-IM-2000-403010 (paratype 1) • 1 dd; same data as for holotype; MCZR-00094 /P (paratype 2) • 16 lv; same data as for holotype; used for DNA sequencing; BAU2944.2 to BAU2944.5, BAU2945.1 to BAU2945.5, BAU2946.1, BAU2947.1 to BAU2947.4, BAU2948.1, BAU2948.2 (paratypes 3–18) • 8 lv; same data as for holotype; CS-PM (paratypes 19–26) • 4 lv; same data as for holotype; FS (paratypes 27–30).

Other material examined

CANARY ISLANDS • 8 dd; Tenerife, Punta de Teno; on stones at low tide; CS-PM • 30 dd; Gran Canaria, Meloneras; low tide; CS-PM • 5 dd; unprecised locality; “Canarie! D. Tomlin 1919”; MCZR-M-11761. MADEIRA • 20 dd; unprecised locality; “ Madera ”, ex Watson collection, labelled as “ Mirulinus watsoni ”; MCZR-M-11715 • 5 dd.; unprecised locality; ex Watson collection; MCZR-M-11715 • 3 dd; unprecised locality; “ Madera ”, ex Nobre collection; MCZR-M-11715.

Description (in parentheses data of the holotype)

SHELL. Shell of medium size for the genus, height 5.2–6.7 (6.5) mm, width 4.1–4.8 (4.8) mm, height/ width ratio 1.20–1.35, conical, shiny in type material. Protoconch of ca 1 whorl 0.23–0.24 (0.24) mm in width, sculptured by one spiral thread. Teleoconch of 5.5–6.0 (5.5) slightly convex whorls. Sculpture of 4–6 (6) spaced abapical spiral cords, smooth or slightly grainy, of about the same strength, and a very evident peripheral cord, slightly shouldered, formed by 4–6 (4) merged cordlets. Fine prosocline growth striae and lamellae, particularly in the interspaces. Suture incised. Base convex and rounded, with 6–7 (7) regularly spaced, flat basal spiral cords; umbilicus closed also in juveniles, covered with a white callus. Aperture quadrangular, with the columellar callus thickened in the lower portion. Interior of the aperture whitish, greyish-greenish, nacreous.

COLOURATION. Colour of protoconch and initial teleoconch whorls whitish, remaining whorls and base bright greenish cream or greenish whitish; spiral cords with alternating spots, whitish or reddish or blackish sutural and peripheral cord articulated in black and white.

SOFT PARTS. Observed in alcohol preserved specimens, no dark terminal strip observed on the creamy band of the snout.

Distribution

Canary Islands, all living specimens collected in the intertidal. The historical records from Madeira in the Monterosato collection need confirmation.

Remarks

Jujubinus swinneni sp. nov. has been reported by Segers et al. (2009: 69, pl. 6 fig. 5) under the name Jujubinus vexationis, a distinct species probably endemic to Madeira. In the Monterosato collection are kept three vials, containing a total of 28 shells, of J. vexationis (probably all from Madeira) labelled “ J. watsoni ”, “ Mirulinus watsoni ”, and “ Trochus striatus ”, respectively. It has also been confused with J. gravinae (e.g., Rolán & Swinnen 2009: figs 33–39; Hernández et al. 2011: 428, fig. 14a–e). Poppe & Goto (1991) reported but did not figure J. gravinae from the Canary Islands (where it is actually absent) probably referring to J. swinneni. The confusion may have been caused by the colouration of J. swinneni that somehow mimics the sutural and peripheral sculpture of J. gravinae (see below). Jujubinus swinneni differs from J. vexationis in its less slender shell with a wider base and for the sculpture of regularly spaced cords similar in size, versus the more numerous and irregularly spaced ones of J. vexationis; additionally, the characteristic pattern with dull colours of the latter allows an easy separation. Jujubinus errinae (endemic to the Messina Strait) also presents a tuberculate sutural cord in the first teleoconch whorls, but with different colouration (spiral cords streaked with red) and marked sculpture (with strong prosocline lamellae in the interspaces) (Smriglio et al. 2016; Giacobbe & Renda 2019). See under J. gravinae for comparative remarks.