Vokesimurex rectaspira, Roland & Virginie, 2015

Roland, Houart & Virginie, Héros, 2015, New species of Muricidae Rafinesque, 1815 (Mollusca: Gastropoda) from the Western Indian Ocean, Zoosystema 37 (3), pp. 481-503 : 483-484

Vokesimurex rectaspira n. sp.

( Figs 3 A-G; 5A; 14A)

TYPE MATERIAL. — Holotype (lv) MNHN-IM-2009-14495 BOLD ID BOMGA023-15, GenBank accession number KP697994 for COI gene KC860506 ( Fig. 3A, B ) and 7 paratypes MNHN: 1 (lv)

IM-2009-14501 BOLD ID BOMGA022-15, GenBank accession number KP697995 for COI gene KC860506 ; 3 (lv) & 3 (dd) IM- 2000-30001; 1 paratype coll. RH (all from type locality).

TYPE LOCALITY. — Southern Madagascar, Southwest of Pointe Barrow, 25°03’S, 44°00’E, 132-153 m [ATIMO VATAE: stn CP3589].

MATERIAL EXAMINED. — Known only from the type material.

DISTRIBUTION. — Southern Madagascar, taken alive at 132- 153 m.

ETYMOLOGY. — Latin, rectaspira , rectus (straight) and spira (spire). This species is named for its flattened spire outline.

DESCRIPTION

Shell small for the genus, up to 41.2 mm in height at maturity (holotype MNHN). Height/width ratio 2.9 (holotype MNHN). Slender, lanceolate, weakly spinose, lightly built. Shoulder ramp strongly sloping, weakly concave.

Beige or light tan with brown or dark brown spiral cords. Aperture glossy white.

Spire high with 2.10 protoconch whorls and teleoconch with up to six weakly convex and weakly shouldered whorls. Suture slightly impressed. Protoconch moderately broad, weakly conical, whorls rounded, last whorl minutely punctate, glossy, maximum width of last whorl 1000 µm and first whorl 700 µm (holotype). Terminal lip heavy, narrow, erect and curved.

Axial sculpture of teleoconch whorls consisting of high, rounded varices and ribs, each varix with a single, short, acute, narrow, narrowly open primary shoulder spine (P1). First whorl with 11 or 12 ribs, second with 9-12, third with 8-10, fourth to last whorl with three narrow, rounded, high varices and two intervariceal, high, narrow ribs. Spiral sculpture of narrow, smooth, primary, secondary and tertiary cords. First and second teleoconch whorls with IP, P1, P2, (S2), P3, P4, third whorl with (adis), IP, P1, (s1), P2, s2, P3, (s3), P4, fourth and fifth with adis, IP, abis, P1, S1, P2, s2, P3, s3, P4, last whorl with adis, IP, abis, P1, s1, P2, s2, P3, s3, P4, s4, P, s5, P6, s6, P7, s7, ADP, ads, MP, ms, ABP, abs, EAB1, eabs1, EAB2, eabs2, EAB3, eabs3, followed by several shallower spiral cords. Only P1 ending as short, acute, narrow variceal shoulder spine.

Aperture moderately small, roundly-ovate. Columellar lip narrow, flaring, smooth. Rim erect, a small portion adherent at adapical extremity. Low parietal tooth at extreme adapical extremity. Anal notch shallow, broad. Outer lip erect, smooth within or with seven very weak, elongate denticles:ID, D1-D6.

Siphonal canal long, narrow, narrowly open.

Operculum dark brown, roundly-ovate with subapical nucleus. Attached with about four growth lines and broad, callused rim.

Radula ( Fig. 14A ) typical for the genus, with a rachidian bearing a long, triangular central cusp, a small lateral denticle and a broad, triangular, medium sized lateral cusp, marginal area smooth. Lateral tooth sickle shaped, broad.

REMARKS

Vokesimurex rectaspira n. sp. differs from the superficially similar V. gallinago fernandesi Houart, 1990 from Mozambique ( Fig. 3H, I ) by having a more regularly-shaped protoconch, with a narrower, more strongly curved terminal lip with slightly more numerous whorls, 2.10-2.15 as opposed to 1.75-2.0 in V. gallinago fernandesi and with a narrower first whorl (width 700 µm vs 900-1100 µm). Vokesimurex rectaspira n. sp. is also more slender with a higher spire consisting of more numerous teleoconch whorls for a similar shell height and also differs by having a flatter as opposed to a more rounded or occasionally weakly concave spire outline in V. gallinago fernandesi , and by having narrower primary spiral cords on the siphonal canal. Another Vokesimurex species occurring in northern Madagascar, namely V. dolichourus (Ponder & Vokes, 1988) ( Fig. 3 J-L) differs also in many ways in its protoconch and teleoconch characters.

Figures

FIG. 3. — A-G, Vokesimurex rectaspira n. sp.; ATIMO VATAE: stn CP3589; A, B, holotype MNHN IM-2009-14495, 41.2 mm; C, D, paratype MNHN IM-2000- 30001, 38.2 mm; E, F, paratype MNHN IM-2000-30001, 24.8 mm; G, protoconch; H, I, Vokesimurex gallinago fernandesi (Houart, 1990); Mozambique, 93-112 m, holotype MNHN IM-2000-0089, 63.2 mm; J-L, Vokesimurex dolichourus (Ponder & Vokes, 1988); J, K, MIRIKY, stn CP3288, 46-54 m, 56.2 mm; L, protoconch; M, N, Vokesimurex aliquantulus n. sp.; MIRIKY, stn CP3206, 70-74 m, holotype MNHN IM-2007-36971, 28.3 mm. Scale bars: G, L, 500 µm.

FIG.14. — Radulae: A, Vokesimurex rectaspira n. sp.; ATIMO VATAE, stn CP3589, paratype MNHN IM-2000-30001; B, C, Flexopteron akainakares n. sp.; ATIMO VATAE, stn DW3515, paratype MNHN IM-2000-30013; D-F, Flexopteron primanova (Houart, 1985); MIRIKY, stn CP3210, scale bar 25 µm; G, Bouchetia vauban- ensis (Houart, 1986); New Caledonia, BIOCAL, stn DW44. Scale bars: A, 100 µm; B, C, 20 µm, D-F, 25 µm; G, 10 µm.