Clavus maestratii, Kilburn, Richard N., Fedosov, Alexander & Kantor, Yuri, 2014

Kilburn, Richard N., Fedosov, Alexander & Kantor, Yuri, 2014, The shallow-water New Caledonia Drilliidae of genus Clavus Montfort, 1810 (Mollusca: Gastropoda: Conoidea), Zootaxa 3818 (1), pp. 1-69 : 48-51

Clavus maestratii new species

( Figs. 24 E, F, 25 A–G)

Drillia (Clavus) fusconitens (non G. B. Sowerby, III, 1901); Bouge & Dautzenberg 1914: 139.? Clavus fusconitens ; Cernohorsky 1978: 153, pl. 54, fig. 10.

Type material. Holotype: New Caledonia, EXPÉDITION MONTROUZIER, Touho, near Baie de Touho, Stn. 1251, 20°46.0’– 20°46.5’S, 165°13’– 165°14.5’E, 6–15 m, MNHN IM–2000–26942; Paratypes: Touho, EXPÉDITION MONTROUZIER, Stn. 1251 (2— MNHN IM–2000–26943); Koumac, EXPÉDITION MONTROUZIER, Stn. 1303, 20°37.7– 20°38.8’S, 164°15.9– 164 °17.1’E, 0–8 m (1— MNHN IM–2000–26944); Stn. 1304, 20°38.6’S, 164°13.2’E, 12–15 m (5— MNHN IM–2000–26945).

Other new caledonian material examined (total 83 lots, 315 spms, including type material):

New Caledonia, EXPÉDITION MONTROUZIER, Koumac Stns. 1286 (2 spms), 1302 (1 spm), 1304 (63 spms), 1305 (11 spms), 1308 (2 spms), 1309 (42 spms), 1311 (1 spm), 1314 (14 spms), 1315 (2 spms), 1321 (1 spm), 1322 (1), 1323 (4 spms); Touho, Stn. 1261 (13 spms);

Nouméa: Campagne d'essais 1987 Stn. DE 34 (1 spm);

LAGON, Stns. 40 (1 spm), 65 (3 spms), 170 (3 spms), 186 (2 spms), 201 (2 spms), 226 (2 spms), 266 (1 spm), 291 (1 spm), 303 (1 spm), 442 (1 spm), 446 (1 spm), 470 (3 spms), 482 (1 spm), 504 (2 spms), 517 (5 spms), 522 (1 spm), 530 (1 spm), 580 (1 spm), 603 (2 spms), 604 (2 spms), 716 (1 spm), 747 (1 spm), 862 (1 spm), 878 (1 spm), 888 (3 spms), 898 (3 spms), 911 (3 spms), 932 (1 spm), 973 (3 spms), 984 (4 spms), 990 (1 spm), 995 (1 spm), 997 (1 spm), 1005 (2 spms), 1007 (3 spms), 1008 (1 spm), 1009 (1 spm), 1024 (2 spms), 1025 (15 spms), 1081 (1 spm), 1087 (1 spm), 1093 (1 spm), 1106 (1 spm), 1111 (1 spm), 1119 (1 spm), 1122 (2 spms), 1128 (1 spm), 1129 (2 spms), 1134 (1 spm), 1137 (1 spm), 1142 (1 spm), 1143 (2 spms), 1145 (1 spm), 1155 (3 spms), 1163 (4 spms), 1165 (1 spm), 1168 (3 spms), 1174 (1 spm), 1181 (1 spm), 1182 (1 spm), 1192 (4 spms), 1205 (7 spms);

PALEO –SURPRISE, north New Caledonia, Stn. DW1396 (1 spm).

Coral Sea, CHALCAL 1, Stn. DC 27 (1 spm).

Etymology. Named in honour of Philippe Maestrati of MNHN, always helpful and friendly to visitors to that institute, and a participant in Koumac and Lifou expeditions.

Distribution. New Caledonia, Coral Sea and probably elsewhere in the tropical central and south Pacific, intertidal (Stn. 1286) to ca 100 m (Stn. 1323), confirmed live to ca 50 m.

Diagnosis. Shell small (to ca 12 mm), breadth/length 0.34–0.40, spire high (0.34–0.38), initially slightly coeloconoid, later cyrtoconoid, base moderately produced, fasciole slight, base obliquely truncate, outer lip slightly alate, anal sinus shallowly to fairly deeply linguiform, constricted by a moderate to large parietal nodule, stromboid notch deep. Whorls initially evenly convex, later ones with periphery at basal third, flattened slightly below suture, ribs not indented by a sulcus. Axial ribs strong, slightly weaker at suture, opisthocline, slightly procurved below suture, markedly sinuous on last whorl, reaching rostrum, in t/s rounded-angular, 8–9 per whorl. Terminal varix strong, slightly preceding outer lip. Microsculpture indistinct. Rostrum with 5–7 declivous spiral ridges. Medium brown to greyish- or orange-brown, ribs often paler, highly glossy.

Description. Shell claviform (breadth/length 0.34–0.40), with acute apex, spire initially slightly coeloconoid, later cyrtoconoid, base moderately produced, and convex-sided with a slight fasciole, aperture (aperture/total length 0.34–0.38), slightly contracted near its base; siphonal canal moderately short, with obliquely truncate base. Outer lip in adult slightly alate, in side view gently convex, with deep stromboid notch, anal sinus shallowly to fairly deeply linguiform, directed slightly adapically, constricted by a moderate to large parietal nodule.

Surface highly glossy. Suture simple to weakly crenulated, shallow. Whorls initially evenly convex, later ones with periphery at basal third of whorl, flattened slightly below suture, ribs not indented by a sulcus. Axial ribs strong, slightly weaker at suture, opisthocline, slightly procurved below suture, markedly sinuous on last whorl, reaching rostrum, in t/s rounded-angular, somewhat asymmetrical, wider than intervals, 8–9 ribs per whorl. Terminal varix strong, suture to base, slightly preceding outer lip, Microsculpture indistinct. Rostrum with 5–7 declivous spiral ridges.

Colour varying from pale brown or greyish-brown to orange brown, ribs usually lighter; occasionally with a dark spire and paler last whorl. Attains ca 12.0 mm.

Protoconch ( Fig. 25 F–G) narrowly domed, of 2.75 smooth whorls, posteriormost 1/4 whorl with fine incremental strongly sinuouse lines. Diameter about 600 Μm, height about 600 Μm. Protoconch-teleoconch transition distinct, marked by thin but distinct axial riblet in the shape of anal sinus and appearance of strong axial definitive rib.

Measurements. Holotype: 11.8 x 4.5 mm; largest and smallest paratypes 12.3 x 4.2 mm and 9.9 x 4.0 mm, respectively.

Radula ( Fig. 24 E, F): Rachidian narrow, length five times exceeds width, anterior edge pointed indistinct. Teeth with large single median cusp. Lateral teeth relatively narrow, arcuate, with 9–10 cusps, 3rd–5th from inner side being the longest and gradually diminishing in length towards outer side, where they evanesce. Marginal teeth relatively short and broad, with poorly pronounced blade, about 1/3 of teeth length. Blade edges not thickened. Accessory limb very weak. About 45 rows of teeth.

Remarks. According to a specimen presented to the MNHN by Bouge, this species is the basis for Bouge & Dautzenberg’s record of Drillia (Clavus) fusconitens (Sowerby, 1901) from New Caledonia. It also appears to be the taxon figured by Cernohorsky (1978) as that species. Clavus fusconitens , for which an earlier name proves to be Drillia (Drillia) quadrasi Boettger, 1895 syn. nov., has a similar highly glossy surface, but is more broadly biconical, with much weaker axial ribs, less convex whorls and a strong fasciole, and is even darker in colour. Two syntypes of D. fusconitens have been examined in the NHMUK (1901.10.3.9–10), and a photograph of a syntype of D. quadrasi was kindly made available by Dr R. Janssen (SMF). The spire in many individuals is encrusted with bryozoans and the apex eroded.

Figures

FIGURE 24. Radulae of Clavus devexistriatu s n. sp., C. hylicos n. sp. and C. maestratii n. sp. A, B. Clavus devexistriatus, New Caledonia, LAGON, Stn. 933, SL 12.8 mm (shell—Fig. 22 C); C, D. Clavus hylikos; New Caledonia, EXPÉDITION MONTROUZIER, Touho Stn. 1260, SL 7.5 mm (shell—Fig. 23 D). E, F. Clavus maestratii, EXPÉDITION MONTROUZIER, Koumac Stn. 1309, SL 9.8 mm (shell—Fig. 25 E).

FIGURE 25. Clavus maestratii n. sp. A, B. Holotype; C. Paratype MNHN IM – 2000 – 26945, SL 10.0 mm; D. Paratype, MNHN IM – 2000 – 26945, 11.8 x 4.3 mm; E. Radula voucher, New Caledonia, EXPÉDITION MONTROUZIER, Koumac Stn. 1309, SL 9.8 mm (radula—Fig. 24 E, F); F, G. New Caledonia, EXPÉDITION MONTROUZIER Koumac, Stn. 1286, SL 5.3 mm.