Okutanius kuroseanus ( Okutani, 1975 ) Kantor & Fedosov & Snyder & Bouchet, 2018

Kantor, Yuri I., Fedosov, Alexander E., Snyder, Martin Avery & Bouchet, Philippe, 2018, Pseudolatirus Bellardi, 1884 revisited, with the description of two new genera and five new species (Neogastropoda: Fasciolariidae), European Journal of Taxonomy 433, pp. 1-57 : 37-40

Okutanius kuroseanus ( Okutani, 1975) gen. et comb. nov.

Figs 4G , 9 A–G

Fusolatirus kuroseanus Okutani, 1975: 193 , pl. 10, fig 21.

Pseudolatirus leucostriatus Kosuge, 1979: 31 , pl. 5, fig. 5, syn. nov.

Fusolatirus kuroseanus – Okutani 2000: 507, pl. 252, fig. 11. — Marais & Kilburn 2010: 127.

Latirus kuroseanus – Mallard & Robin 2005: caption on pl. 45.

Pseudolatirus kuroseanus – Mallard & Robin 2017: 153.

Type material

JAPAN: holotype of of F. kuroseanus, Kurose Bank , off Izu islands, south of Honshū, 33°23.5′ N, 139°36.2′ E, 260 m ( NSMT Mo 69575) (illustrated by Higo et al. 2001: 87); holotype of P. leucostriatus (said to be off Midway Island, 32°02′ N, 173°06′ W, 365 m, but label of holotype says 29°46.4′ N, 179°02.9′ E, 265 m) in the Institute of Malacology, Tokyo ( IMT 79-18) [examined]; paratype, same location as holotype, said to be donated to USNM.

Sequenced material

PAPUA NEW GUINEA, NEW IRELAND: KAVIENG 2014: 1 lv, stn CP4503, 02°30′ S, 150°44′ E, 191–200 m ( MNHN IM-2013-59070).

Other material examined

TAIWAN: TAIWAN 2000: 2 dd, stn DW05, 23°41′ N, 119°56′ E, 213–236 m; 2 dd, stn DW34, 22°01′ N, 120°36′ E, 240–246 m; 25 dd, stn DW36, 21°54′ N, 120°36′ E, 300– 331 m.

PHILIPPINES: 2 spms, Panglao, Bohol, tangle nets, 160 m, ( ANSP 425326); 2 spms, off Aliguay I., Mindanao, 150 m ( ANSP 425322); 1 spm, Bohol, Balicasag, 240 m ( ANSP 425324); 1 spm, Philippine Is, tangle nets ( ANSP 425325); 1 spm, Balicasag I., Bohol, tangle nets, 240 m ( ANSP 425327); 1 spm, Siquijor I., tangle nets, 150 m ( ANSP 425323).

ARAFURA SEA: KARUBAR: 1 lv, 13 dd, stn DW15, 05°17′ S, 132°41′ E, 212– 221 m.

SOLOMON ISLANDS: SALOMON 1: 1 dd, stn DW1765, 08°43′ S, 160°07′ E, 325–380 m; 1 dd, stn DW1812, 09°46′ S, 160°52′ E, 222– 246 m.

NEW CALEDONIA: “ Vauban ” 1978–79: 1 dd, stn DR37, 22°32′ S, 166°26′ E, 175– 250 m. – BIOCAL: 1 dd, stn DW81, 20°29′ S, 166°47′ E, 430–470 m; 1 juv. Lv, stn CP105, 21°31′ S, 166°22′ E, 330– 335 m. – BIOGEOCAL: 3 dd, stn DW253, 21°32′ S, 166°29′ E, 310– 315 m. – MUSORSTOM 4: 1 dd, stn DW181, 18°57′ S, 163°22′ E, 350 m. – BATHUS 1: 1 dd, stn DW655, 21°17′ S, 165°57′ E, 375 m; 4 dd, stn DW688, 20°33′ S, 165°00′ E, 270–282 m; 2 dd, stn DW689, 20°33′ S, 165°00′ E, 260– 265 m. – BATHUS 4: 1 dd, stn DW886, 21°01′ S, 164°28′ E, 250–300 m; 1 dd, stn DW887, 21°07′ S, 164°28′ E, 320– 344 m. – SMIB 4: 1 dd, stn DW44, 24°46′ S, 168°08′ E, 270– 300 m. – SMIB 5: 1 dd, stn DW90, 22°19′ S, 168°42′ E, 340 m. – SMIB 8: 1 dd, stn DW160, 24°47′ S, 168°08′ E, 280– 282 m.

LOYALTY RIDGE: MUSORSTOM 6: 2 lv, 3 dd, stn DW391, 20°47′ S, 167°06′ E, 390 m; 1 dd, stn DW397, 20°47′ S, 167°05′ E, 380 m; 1 lv, 1 dd, stn DW398, 20°47′ S, 167°06′ E, 370 m; 1 dd, stn DW418, 20°42′ S, 167°03′ E, 283 m; 3 dd, stn DW459, 21°01′ S, 167°31′ E, 425 m; 3 dd, stn DW480, 21°08′ S, 167°56′ E, 380 m; 1 dd, stn DW481, 21°22′ S, 167°50′ E, 300 m; 1 dd, stn DW482, 21°21′ S, 167°47′ E, 375 m; 2 dd, stn DW487, 21°23′ S, 167°46′ E, 500 m.

VANUATU: MUSORSTOM 8: 1 dd, stn DW1059, 16°13′ S, 167°21′ E, 408–430 m; 1 dd, stn DW1065, 16°16′ S, 167°21′ E, 360– 419 m.

WALLIS AND FUTUNA: MUSORSTOM 7: 1 dd, stn DW496, 14°20′ S, 178°04′ W, 250–330 m (Futuna I.); 1 dd, stn DW509, 14°15′ S, 178°11′ W, 200–240 m (Futuna I.); 1 dd, stn DW523, 13°12′ S, 176°16′ W, 455–515 m (Wallis I.); 1 dd, stn DW569, 12°30′ S, 176°51′ W, 300–305 m (Waterwitch Bank); 1 dd, stn DW571, 12°31′ S, 176°52′ W, 502–508 m (Waterwitch Bank); 1 dd, stn DW610, 13°21′ S, 176°09′ W, 286 m (Wallis I.); 1 dd, stn DW626, 11°54′ S, 179°32′ W, 597–600 m (Bayonnaise Bank).

FIJI: BORDAU 1: 1 lv, 2 dd, stn DW1469, 19°40′ S, 178°10′ W, 314–377 m; 1 lv; stn DW1497, 18°44′ S, 178°25′ W, 335– 350 m.

TONGA: BORDAU 2: 2 dd, stn DW1535, 21°43′ S, 175°18′ W, 268 m; 3 dd, stn DW1567, 21°02′ S, 175°19′ W, 351–356 m; 1 dd, stn DW1583, 18°37′ S, 174°03′ W, 327–360 m; 1 lv (?), 1 dd, stn DW1587, 18°37′ S, 173°54′ W, 309–400 m; 1 dd, stn DW1589, 18°39′ S, 173°54′ W, 281 m; 1 lv (?), stn DW1595, 19°03′ S, 174°19′ W, 523–806 m; 1 dd, stn DW1602, 20°49′ S, 174°57′ W, 263–320 m; 1 dd, stn DW1605, 22°17′ S, 175°16′ W, 441 m; 1 lv, stn DW1607, 22°15′ S, 175°23′ W, 356–367 m; 1 lv (?), stn DW1630, 23°23′ S, 176°18′ W, 360 m; 1 lv (?), stn DW1636, 21°44′ S, 175°20′ W, 321– 331 m.

CHRISTMAS ISLAND: 2 dd, off NE point, 10°25′ S, 105°42′ E, 183 m, coll. R. Kirkpatrick 1916 ( AMS C324273).

RÉUNION: MD32: 1 dd, stn CP129, 20°51′ S, 55°36′ E, 290–300 m; 1 dd worn, stn DC136, 20°46′ S, 55°36′ E, 915– 922 m.

SOUTH AFRICA: 1 dd, former Transkei, off Port Grosvenor, 29°57.4′ S, 31°26.4′ E, 105 m (NM C636); 1 lv (?), former Transkei, off Mtamvuna River, 31°08.4′ S, 30°16.6′ E, 160 m (NM C9652); 2 dd, Zululand, SE of Port Durnford, 29°05.8′ S, 32°09.4′ E, 165 m (NM S903); 1 dd, Zululand, SE of Port Durnford, 29°04.6′ S, 32°09.0′ E, 142 m (NM D7822).

Description

Shell fusiform, up to 28 mm in length. Protoconch acutely conical, multispiral, of 3 smooth, weakly convex whorls, with several slightly arcuate axial riblets on last ½ whorl ( Fig. 9C ). Protoconch diameter 870 µm, exposed height 1000 µm. Teleoconch with regularly convex whorls, without imbricated subsutural spiral ridge, with long siphonal canal; aperture with weak columellar plication, and indistinct parietal tooth; spiral sculpture of unevenly arranged cords of uneven strength; axial ribs aligned along the spire. Background colour from creamy light to yellowish brown, axial ribs brown, primary spiral cords white.

Radula ( Fig. 4G ) examined in two specimens, from Fiji (BORDAU 1, stn DW1497) and from the New Ireland (MNHN IM-2013-59070, 18.1 mm) (shell: Fig. 9A ). They are very similar and that from the New Ireland specimen is illustrated and described. Radula narrow, distance between outer edges of lateral teeth about 70 µm (1.34% of AL). Lateral teeth broad, slightly arcuate, with strongly attenuated outer anterior corner, producing long ‘handle’. Lateral teeth with outermost small cusp, on most rows overlaid by following major cusp and not seen on ventral view (marked by white arrow), five almost equal, closely spaced, cusps, outer one more clearly separated from the rest, and one smaller inner cusp. Central tooth trapezoid, with three short blunt cusps, central slightly longer. Distinct transverse folds of the membrane situated serially between rows of lateral teeth, reaching anterior margin of central tooth.

Distribution

Southwest Pacific Ocean, Indian Ocean to KwaZulu-Natal, in 150–620 m, alive in 150– 400 m.

Remarks

This distinct, medium-sized species is similar to Granulifusus tatianae sp. nov.; for differences, see the description of the latter. It also resembles Okutanius ellenae gen. et sp. nov., but can be easily differentiated from the latter species by the colour pattern.

Figures

Fig. 4. Radulae of species of Granulifusus and Okutanius gen. nov.A. Granulifusus discrepans (Kuroda & Habe, 1961), shell, see Fig. 3D (MNHN IM-2013-46327). B. Granulifusus williami (Poppe & Tagaro, 2006), comb. nov., shell, see Fig. 3H (MNHN IM-2013-58726). C–D. Granulifusus jeanpierrevezzaroi (Cossignani, 2017) comb. nov., shell, see Fig. 5B–D, arrow points to regularly spaced folds of the radular membrane (MNHN IM-2007-34593). E. Granulifusus annae sp. nov., New Caledonia, BATHUS 1, stn CP669, 20°57′ S, 165°35′ E, 255–280 m, shell, see Fig. 6F. F. Granulifusus tatianae sp. nov., Loyalty Ridge, MUSORSTOM 6, stn DW473, 21°09′ S, 167°55′ E, 236 m. G. Okutanius kuroseanus (Okutani, 1975) gen. et comb. nov., New Ireland, shell, see Fig. 9A (MNHN IM-2013-59070). H. Okutanius ellenae gen. et sp. nov., New Caledonia, NORFOLK 1, stn DW1658, 23°26′ S, 167°50′ E, 320–336 m, shell, see Fig. 10H).

Fig. 9. A–G. Okutanius kuroseanus (Okutani, 1975) gen. et comb. nov. A. New Ireland, KAVIENG 2014, stn CP4503, 02°30′ S, 150°44′ E, 191–200 m, SL 18.1 mm, sequenced specimen; for radula, see Fig. 4G (MNHN IM-2013-59070). B. BORDAU 1, stn DW1469, 19°40′ S, 178°10′ W, 314–377 m, SL 15.9 mm. C. Protoconch, New Caledonia, BIOCAL, stn CP105, 21°31′ S, 166°22′ E, 330–335 m. D–E. Loyalty Ridge, MUSORSTOM 6, stn DW391, 20°47′ S, 167°06′ E, 390 m. D. SL 17.3 mm. E. SL 22.3 mm. F. Loyalty Ridge, MUSORSTOM 6, stn DW398, 20°47′ S, 167°06′ E, 370 m, SL 28.1 mm. G. Taiwan. TAIWAN 2000, stn DW34, 22°02′ N, 120°36′ E, 246 m, SL 23.4 mm. H–I. Okutanius aikeni (Lussi, 2014) gen. et comb. nov., holotype, SL 25.6 mm. A–B, D–G at the same scale, H–I not to scale.