Uroptychus alcocki Ahyong & Poore, 2004

Baba, Keiji, 2018, Chirostylidae of the Western and Central Pacific: Uroptychus and a new genus (Crustacea: Decapoda: Anomura), Tropical Deep-Sea Benthos (Mémoires du Muséum national d'Histoire naturelle 212), pp. 1-612 : 49-53

Uroptychus alcocki Ahyong & Poore, 2004

Figure 9

Uroptychus alcocki Ahyong & Poore, 2004: 15 , fig. 2. — Baba 2005: 28, fig. 6. — Poore et al. 2011: 328, pl.6, fig. A.

Uroptychus brevirostris — Baba 1973: 117 (Not U. brevirostris Van Dam, 1933 ).

? Uroptychus cavirostris — Van Dam 1933: 22, figs 33, 34 (see remarks).

TYPE MATERIAL — Holotype: Australia, Southeast of Ballina , New South Wales, female ( AM P31412 ). [not examined]

MATERIAL EXAMINED — Solomon Islands. SALOMON 1 Stn DW1742, 11°29.4’S, 159°57.4’E, 366-421 m, 23.IX.2001, 1 ♂ 4.5 mm, 1 ♀ 3.1 mm (MNHN-IU-2014-17160) . – Stn DW1854, 9°46.4’S, 160°52.9’S, 229-260 m, 7.X.2001, 1 ♂ 5.3 mm, 1 ♀ 5.2 mm (MNHN-IU-2014-17161) . – Stn DW1856, 9°46.4’S, 160°52.3’E, 254-281 m, 7.X.2001 ,1 ov. ♀ 5.1 mm (MNHN-IU-2014-17162) . New Caledonia, Chesterfield Islands.CHALCAL 1 Stn CP08, 19°43.80’S, 158°35.25’E, 348 m, 19.VII.1984, 4 ♂ 5.0- 5.5 mm, 2 ov. ♀ 5.0, 5.6 mm (MNHN-IU-2014-17163) . MUSORSTOM 5 Stn DW256, 25°18.0’S, 159°52.50’E, 290-300 m, 7.X.1986, 1 ♂ 3.7 mm (MNHN-IU-2014-17164) . – Stn DW301, 22°06.90’S, 159°24.60’E, 487-610 m, with coral of Chrysogorgiidae (Calcaxonia) , 12.X.1986, 2 ♀ 4.8, 4.9 mm MNHN-IU-2014-17165) . – Stn CP307, 22°11.07’S, 159°24.07’E, 350- 345 m, with coral Chrysogorgiidae (Calcaxonia) , 12.X.1986, 1 ♂ 4.5 mm, 1 ov. ♀ 5.2 mm (MNHN-IU-2014-17166) . – Stn CP309, 22°10.20’S, 159°22.80’E, 340 m, 12.X.1986, 1 ov. ♀ 5.0 mm (MNHN-IU-2014-17167) . – Stn CP315, 22°25.32’S, 159°27.40’E, 330-335 m, with coral Chrysogorgiidae (Calcaxonia) , 13.X.1986, 1 ov. ♀ 6.0 mm (MNHN-IU-2014-17168) . – Stn DW337, 19°53.80’S, 158°38.00’E, 412-430 m, with coral Chrysogorgiidae (Calcaxonia) , 15.X.1986, 3 ♂ 3.5-5.1 mm, 3 ov. ♀ 5.3-6.1 mm (MNHN-IU-2014-17169) . – Stn DC361, 19°52.50’S, 158°38.10’E, 400 m, 19.X.1986, 1 ♂ 3.0 mm (MNHN-IU-2014-17170) , 1 ov. ♀ 5.8 mm (MNHN-IU-2014-17171) . – Stn DC371, 19°54.85’S, 158°38.17’ E, 350 m, Chrysogorgia sp. ( Calcaxonia , Chrysogorgiidae ), 20.X.1986, 1 ♂ 4.1 mm (MNHN-IU-2014-17172) . – Stn DC378, 19°53.74’S, 158°38.30’E, 355 m, 20.X.1986, 1 ♀ 4.1 mm ( MNHN- IU-2014-17173) . New Caledonia. BIOCAL Stn DW37, 23°00’S, 167°16’E, 350 m, 30.VIII.1985, 1 ♂ 5.2 mm, 1 ov. ♀ 5.3 mm, 1 ♀ 4.8 mm ( MNHN- IU-2014-17175) . – Stn DW38, 23°00’S, 167°15’E, 360 m, 30.VIII.1985, 2 ♂ 4.0, 4.5 mm (MNHN-IU-2014-17176) . – Stn CP110, 22°12.38’S, 167°06.43’E, 275 m, 9.IX.1985, 1 ov. ♀ 3.8 mm (MNHN-IU-2014-17177) . SMIB 1 Stn DW02, 22°51.9’S, 167°13’E, 415 m, 5.II.1986, 1 ♂ 4.9 mm, 5 ov. ♀ 4.9-5.9 mm, 1 ♀ 5.5 mm (MNHN-IU-2014-17178) . SMIB 2 Stn DW03, 22°54’S, 167°15’E, 412-428 m, 1.IX.1986, 1 ♂ 4.9 mm, 3 ov. ♀ 4.9-5.4 mm, 1 ♀ 5.4 mm (MNHN-IU-2014-17179) . – Stn DW05, 22°56’S, 167°14’E, 398-410 m, 17.IX.1986, 13 ♂ 3.3-5.7 mm, 17 ov. ♀ 4.0- 5.3 mm, 4 ♀ 4.2-5.3 mm ( MNHN- IU-2014-17180) . – Stn DW06, 22°56’S, 167°16’E, 442-460 m, 17.IX.1986, 3 ♂ 5.0- 5.4 mm,1 ov. ♀ 5.6 mm, 1 ♀ 2.9 mm (MNHN-IU-2014-17181) . – Stn DW08, 22°53’S, 167°14’E, 435-447 m, 18.IX.1986, 3 ♂ 4.6-4.8 mm, 2 ov. ♀ 4.8, 4.9 mm, 3 ♀ 4.4-5.0 mm (MNHN-IU-2014-17182) . – Stn DW14, 22°53’S, 167°13’E, 405-444 m, 18.IX.1986, 1 ♂ 5.3 mm, 1 ov. ♀ 4.7 mm (MNHN-IU-2014-17183) . SMIB 3 Stn DW08, 24°45.2’S, 168°08’E, 233 m, 21.V.1987, 1 ♂ 4.3 mm (MNHN-IU-2014-17184) . – Stn DW28, 22°47’S, 167°12’E, 394 m, 25.V.1987, 3 ov. ♀ 5.3-5.4 mm, 1 ♀ 5.9 mm ( MNHN- IU-2014-17185) . – Stn DW30, 22°58’S, 167°22’E, 648 m, 25.V.1987, 1 ♂ 3.8 mm, 2 ov. ♀ 3.7, 4.3 mm (MNHN-IU-2014-17186) . MUSORSTOM 4 Stn DW183, 19°01.80’S, 163°25.80’E, 280 m, 18.IX.1985, 1 ov. ♀ 4.2 mm (MNHN-IU-2014-17187) . – Stn DW210, 22°44’S, 167°09’E, 340-345 m, 28. IX.1985, 1 ♂ 4.7 mm, 1 ♀ 4.0 mm (MNHN-IU-2014-12784) , 1 ♀ 3.4 mm (MNHN-IU-2014-12785) . – Stn DW211, 22°46.0’S, 167°09.8’E, 370 m, 28. IX.1985, 1 ov. ♀ 4.0 mm (MNHN-IU-2014-17188) . – Stn DW212, 22°47.4’S, 167°10.5’E, 375-380 m, with coral Chrysogorgiidae (Calcaxonia) , 28. IX.1985, 6 ♂ 4.2-5.3 mm, 4 ov. ♀ 4.9-5.7 mm (MNHN-IU-2014-17189) . – Stn CP213, 22°51.3’S, 167°12.0’E, 405-430 m, with coral Chrysogorgiidae (Calcaxonia) , 28.IX.1985, 14 ♂ 4.0-6.0 mm, 21 ov. ♀ 4.6-6.1 mm, 3 ♀ 4.5-5.9 mm (MNHN-IU-2014-17190) . – Stn CP214, 22°53.8’S, 167°13.9’E, 425- 440 m, 28.IX.1985, 1 ♂ 5.2 mm, 1 ov. ♀ 5.7 mm, 1 ♀ 4.2 mm (MNHN-IU-2014-17191) . – Stn DW222, 22°57.6’S, 167°33.0’E, 410-440 m, with coral Chrysogorgiidae (Calcaxonia) , 30.IX.1985, 1 ov. ♀ 4.4 mm, 2 ♀ 3.6, 4.6 mm (MNHN-IU-2014-17192) , 1 ♂ 5.1 mm MNHN-IU-2014-17193) , 1 ♂ 4.3 mm (MNHN-IU-2014-17194) , 3 ♂ 4.7-5.0 mm,2 ov. ♀ 5.0, 5.3 mm, 2 ♀ 4.7, 4.7 mm (MNHN-IU-2014-17195) . – Stn DW226, 22°47.2’S, 167°21.6’E, 395 m, 30.IX.1985, 2 ♂ 3.9, 4.0 mm (MNHN-IU-2014-17196) . – Stn DW234, 22°15.4’S, 167°08.3’E, 350-365 m, 2.XII.1985, 1 ov. ♀ 3.4 mm ( MNHN- IU-2014-17197) . BATHUS 1 Stn CP656, 21°13.17’S, 165°53.98’E, 452-460 m, 12.III.93, 1 ♂ 4.9 (MNHN-IU-2014-17198) . – Stn CP670, 20°54’S, 165°53’E, 394-397 m, 14.III.1993, 3 ♂ 4.5-4.8 mm (MNHN-IU-2014-17199) . – Stn CP701, 20°57’S, 165°35’E, 302-335 m, 18.III.1993, 1 ♂ 4.3 mm, 1 ov. ♀ 3.8 mm, 1 ♀ 5.3 mm (MNHN-IU-2014-17200) . – Stn CP710, 21°43.16’S, 166°36.35’E, 320-386 m, 19.III.1993, 1 ♂ 4.0 mm ( MNHN- IU-2014-17201) . BATHUS 2 Stn DW717, 22°44’S, 167°16’E, 350-393 m, 11.V.1993, 1 ♀ 4.7 mm (MNHN-IU-2014-17202) . – Stn DW718, 22°46.70’S, 167°14.45’E, 430-436 m, 11.V.1993, 1 ♀ 4.7 mm (MNHN-IU-2014-17203) . – Stn DW729, 22°52.42’S, 167°11.90’E, 400 m, 12.V.1993, 4 ♂ 4.4-5.1 mm, 2 ov. ♀ 4, 8, 4.9 mm, 2 ♀ 4.5, 4.8 mm (MNHN-IU-2014-17204) . – Stn CP742, 22°33’S, 166°25’E, 340-470 m, 14.V.1993, 1 ♂ 4.1 mm ( MNHN- IU-2014-17205) . BATHUS 3 Stn CP805, 23°41’S, 168°01’E, 278-310 m, 27.XI.1993, 1 ♀ 5.2 mm (MNHN-IU-2014-17206) . – Stn CP806, 23°42,31’ S, 168°00,52’E, 308-312 m, 27.XII.1993, 1 ov. ♀ 4.9 mm (MNHN-IU-2014-17207) . – Stn DW829, 23°21’S, 168°02’E, 386-390 m, 29.XI.1993, 1 ♀ 4.4 mm (MNHN-IU-2014-17208) . – Stn DW830, 23°20’S, 168°01’E, 361-365 m, 29.XI.1993, 2 ♂ 4.4, 4.9 mm, 1 ov. ♀ 4.1 mm (MNHN-IU-2014-17209) . BATHUS 4 Stn CP899, 20°16.68’S, 163°50.26’E, 500-600 m, 3.VIII.1994, 3 ♂ 3.9-5.0 mm, 1 ov. ♀ 4.2 mm (MNHN-IU-2014-17210) . – Stn CP900, 20°16.74’S, 163°50.06’E, 580 m, 3.VIII.1994, 1 ♂ 4.5 mm (MNHN-IU-2014-17211) . – Stn CP905, 19°02.45’S, 163°15.65’E, 294-296 m, 4.IV.1994, 2 ♂ 4.1, 5.0 mm, 1 ♀ 5.2 mm (MNHN-IU-2014-17212) . VAUBAN 1978-1979, no data, 8 ov. ♀ 4.6-6.1 mm, 1 ♀ 5.2 mm (MNHN-IU-2014-17213) . – Stn DR15, 22°49’ S, 167°12.0’E, 390-395 m, 10.IV.1978, 8 ♂ 4.1-5.4 mm, 3 ov. ♀ 4.3-5.8 mm, 2 ♀ 3.2, 5.0 mm (MNHN-IU-2014-17214) . – Stn DR24, 22°48’S, 167°09’E, 355-360 m, on unidentified coral, 13.IV.1978, 1 ♂ 5.4 mm, 1 ♀ 4.5 mm (MNHN-IU-2014-17215) . LAGON DW444, 18°15’S, 162°59’E, 300- 350 m, 28.II.1985, 1 ♂ 5.9 mm, 1 ov. ♀ 5.7 mm (MNHN-IU-2014-17174) . – DW423, 22°46’S, 167°13’E, 405 m, 24.I.1985 ,3 ov. ♀ 4.8-5.5 mm, 1 ♀ 2.4 mm (MNHN-IU-2014-17216) . Southern New Caledonia. SMIB 2 Stn DW05, 22°56’S, 167°14’E, 398-410 m, 17.IX.1986, 1 ♂ 4.9 mm (MNHN-IU-2014-17218) . No Stn, 23°00’S, 167°17’E, Dredge, 430 m, 6. IV.1976,coll.A. Michel, 2 ♂ 4.3, 4.4 mm, 1 ♀ 4.6 mm (MNHN-IU-2010-5480) . – No Stn, 22°40’S, 167°10’E, 200-350 m, 7-10.X.1986, 1 ♀ 4.5 mm (MNHN-IU-2014-17217) . New Caledonia, Isle of Pines. 360 m, 13.IV.1978, on hydroids, coll. A. Intes, 3 ov. ♀ 5.3-6.0 mm (MNHN-IU-2014-17219) . New Caledonia, Norfolk Ridge.CHALCAL 2 Stn CP26, 23°18.15’S, 168°03.58’E, 296 m,on coral Chrysogorgiidae (Calcaxonia) , 31.X.1986, 2 ♂ 4.1, 4.5 mm, 2 ov. ♀ 4.5, 6.4 mm, 1 ♀ 4.5 mm (MNHN-IU-2014-17220) . – Stn CP 27, 23°15.29’S, 168°04.55’E, 289 m, 3.X.1986, 1 ov. ♀ 4.9 mm MNHN-IU-2014-17221) , 3 ♂ 4.6-5.3 mm, 7 ov. ♀ 4.5-5.7 mm, 1 ♀ 4.8 mm (MNHN-IU-2014-17222) . – Stn DW81, 23°19.6’S, 168°03.4’E, 311 m, 31.X.1986, 2 ♀ 2.6, 4.6 mm (MNHN-IU-2014-17223) . SMIB 5 Stn DW72, 23°42.0’S, 168°00.8’E, 280-400 m, 7.IX.1989, 1 ♂ 5.2 mm (MNHN-IU-2014-17224) . – Stn DW87, 22°18.7’S, 168°41.3’ E, 335-370 m, 13.IX.1989, 3 ♂ 3.0- 3.4 mm, 4 ov. ♀ 4.6-5.8 mm (MNHN-IU-2014-17225) . – Stn DW97, 23°01.1’S, 168°18.0’E, 240-300 m, 14.IX.1989, 1 ♂ 3.1 mm (MNHN-IU-2014-17226) . – Stn DW101, 23°21.2’S, 168°04.9’E, 270-285 m, 14. IX.1989, 1 ov. ♀ 4.3 mm (MNHN-IU-2014-17227) . – DW102, 23°19.6’S, 168°04.7’E, 290-305 m, 14.IX.1989, 2 ♂ 5.1, 5.5 mm, 1 ov. ♀ 3.8 mm ( MNHN- IU-2014-17228) . – Stn DW103, 23°16’S, 168°04.8’E, 300-315 m, 14.IX.1989, 1 ♂ 5.3 mm, 4 ov. ♀ 4.0- 5.1 mm, 1 ♀ 3.2 mm (MNHN-IU-2014-17229) . – Stn DW104, 23°15.7’S, 168°04.4’ E, 305-335 m, 14.IX.1989, 1 ov. ♀ 4.9 mm (MNHN-IU-2014-17230) . – MUSORSTOM 4 no station data, Banc Alis, 250 m, rock, 13.IX.1985, 1 ♂ 3.0 mm, 1 ov. ♀ 3.3 mm (MNHN-IU-2014-17231) . SMIB 8 Stn DW181, 23°17.74’ S, 168°04.82’E, 311-330 m, 31.I.1993, 1 ov. ♀ 4.7 mm (MNHN-IU-2014-17232) . – Stn DW183, 23°18.27’S, 168°04.95’E, 330-367 m, 31.I.1993, 1 ♂ 6.0 mm, 1 ov. ♀ 4.8 mm ( MNHN- IU-2014-17233) . – Stn DW185, 23°15’S, 168°04.3’E, 311-355 m, 31.I.1993, 1 ♀ 5.1 mm (MNHN-IU-2014-17234) . – Stn DW190, 23°18’S, 168°05’E, 305- 310 m, 31.I.1993, 2 ov. ♀ 4.7, 5.2 mm (MNHN-IU-2014-17235) . – Stn DW197, 22°51.27’S, 168°12.54’E, 414-436 m, 1.II.1993, 3 ov. ♀ 3.3-3.7 mm (MNHN-IU-2014-17236) . – Stn DW198, 22°51.6’S, 167°12.4’E, 414-430 m, 1.II.1993, 1 ov. ♀ 5.7 mm (MNHN-IU-2014-17237) . NORFOLK 1 Stn DW1651, 23°27.3’S, 167°50.4’ E, 276-350 m,? Acanthogorgiidae (Acanthogorgiidae) , 19.VI.2001, 1 ♂ 4.8 mm, 1 ov. ♀ 6.8 mm (MNHN-IU-2014-17238) . – Stn DW1653, 23°28’S, 167°51’E, 328-340 m, 19.VI.2001, 1 ♂ 3.3 mm, 1 ov. ♀ 7.2 mm (MNHN-IU-2014-17239) . – Stn DW1654, 23°26’S, 167°52’E, 366- 560 m, 19.VI.2001, 1 ♂ 5.2 mm, 1 ov. ♀ 5.8 mm (MNHN-IU-2014-17240) . – Stn DW1657, 23°26’S, 167°52’E, 305-332 m, 19.VI.2001, 1 ♂ 5.7 mm (MNHN-IU-2014-17241) . – Stn CP1671, 23°41’S, 168°00’E, 320-397 m, alcyonacean Chironephthya sp.( Alcyoniina : Nidaliidae ) , 21.VI.2001, 2 ov. ♀ 4.9, 5.3 mm (MNHN-IU-2014-17242) . – Stn DW1729, 23°20’S, 168°16’E, 340-619 m, 27.VI.2001, 1 ov. ♀ 6.6 mm (MNHN-IU-2014-17243) . – Stn DW1733, 22°56’ S, 167°15’E, 427-433 m, 28.VI.2001, 3 ♂ 4.7-4.9 mm, 5 ov. ♀ 4.3-5.3 mm (MNHN-IU-2014-17244) . – Stn DW1736, 22°51’S, 167°12’E, 383-407 m, 28.VI.2001, 10 ♂ 3.2-5.9 mm, 7 ov. ♀ 4.3-5.7 mm (MNHN-IU-2014-17245) . – Stn DW1737, 22°52’S, 167°12’E, 400 m, with coral Chrysogorgiidae (Calcaxonia) , 28.VI.2001, 3 ♂ 3.3-5.3 mm, 6 ov. ♀ 4.2-5.2 mm (MNHN-IU-2014-17246) . NORFOLK 2 Stn DW2024, 23°28’S, 167°51’E, 370-371 m, 21.X.2003, 1 ♂ 4.2 mm, 2 ov. ♀ 3.8, 5.1 mm (MNHN-IU-2014-17247) . – Stn CP2038, 23°41.86’S, 168°00.28’E, 290-330 m, 23.X.2003, 1 ov. ♀ 4.9 mm (MNHN-IU-2014-17248) . – Stn CP2130, 23°15.90’S, 168°13.54’E, 375-427 m, 2.XI.2003, 1 ov. ♀ 5.2 mm (MNHN-IU-2014-17249) . – Stn CP2139, 23°00.68’S, 168°22.60’ E, 372-393 m, 3.XI.2003, 1 ov. ♀ 5.2 mm (MNHN-IU-2014-17250) . – Stn CP2154, 22°49.90’S, 167°12.60’E, 410-423 m, 5.XI.2003, 11 ♂ 4.3-5.3 mm, 18 ov. ♀ 3.7-5.2 mm (MNHN-IU-2014-17251) . – Stn CP2160, 22°41.81’S, 167°09.70’E, 313-315 m, 6.XI.2003, 1 ♂ 4.2 mm ( MNHN- IU-2014-17252) . BERYX 11 Stn CP45, 23°40.27’S, 168°00.95’E, 270-290 m, 20.X.1992, 1 ov. ♀ 5.1 mm (MNHN-IU-2014-17253) . New Caledonia. Loyalty Ridge. MUSORSTOM 6 Stn DW392, 20°47.32’S, 167°04.60’E, 340 m, with Acanella sp. ( Calcaxonia : Isididae ), 13.II.1989, 1 ov. ♀ 3.3 mm (MNHN-IU-2014-17254) . – Stn DW406, 20°40.65’S, 167°06.80’ E, 373 m, 15.II.1989, 1 ov. ♀ 6.0 mm (MNHN-IU-2014-17255) . – Stn DW407, 20°40.70’ S, 167°06.60’E, 360 m, with coral Chrysogorgiidae (Calcaxonia) , 15.II.1989, 1 ♂ 4.3 mm, 1 ♀ 3.6 mm (MNHN-IU-2014-17256) . – Stn CP409, 20°41.05’S, 167°07.25’E, 385 m, 15.II.1989, 1 ov. ♀ 5.8 mm (MNHN-IU-2014-17257) . – Stn CP419, 20°41.65’S, 167°03.70’E, 283 m, 16.II.1989, 1 ov. ♀ 3.6 mm, 1 ♀ 3.6 mm (MNHN-IU-2014-17258) . – Stn CP438, 20°23.00’S, 166°20.10’E, 800 m, 18.II.1989, 1 ov. ♀ 3.8 mm (MNHN-IU-2014-17259) . – Stn DW472, 21°08.60’S, 167°54.70’E, 300 m, 22.II.1989, 3 ♂ 2.8-5.7 mm, 3 ov. ♀ 3.9-6.2 mm, 1 ♀ 4.0 mm (MNHN-IU-2014-17260) . – Stn DW479, 21°09.13’S, 167°54.95’E, 310 m, 22.II.1989, 1 ov. ♀ 5.8 mm (MNHN-IU-2014-17261) . New Caledonia, Hunter and Matthew Islands. VOLSMAR Stn DW16, 22°25.1’S, 171°40.7’E, 420-500 m, 3.VI.1989, 2 ♂ 4.0, 4.1 mm (MNHN-IU-2014-17274) . – Stn DW39, 22°20.5’S, 168°43.5’E, 280-305 m, 8.VI.1989, 1 ♂ 4.8 mm, 2 ov. ♀ 4.2, 4.3 mm (MNHN-IU-2014-17275) . Vanuatu. MUSORSTOM 8 Stn CP963, 20°20.10’S, 169°49.08’E, 400-440 m, 21.IX.1994, 1 ov. ♀ 4.1 mm (MNHN-IU-2014-17262) . – Stn CP982, 19°21.80’S, 169°26.47’E, 408-410 m, 23.IX.1994, 2 ♂ 4.0, 4.7 mm, 2 ov. ♀ 4.9-5.4 mm, 1 ♀ 4.0 mm (MNHN-IU-2014-17263) . – Stn CP1024, 17°48.21’S, 168°38.77’E, 335-370 m, 28.IX.1994, 1 ♂ 5.7 mm, 2 ov. ♀ 4.1, 5.5 mm, 1 ♀ 6.4 mm ( MNHN- IU-2014-17264) . – Stn DW1058, 16°12.03’S, 167°20.80’E, 319 m, with Acanella sp. ( Calcaxonia : Isididae ), 2.X.1994, 1 ♂ (carapace lost) ( MNHN- IU-2014-17265) . – Stn DW1060, 16°13.82’S, 167°20.80’E, 375- 394 m, 2.X.1994, 1 ♂ 5.5 mm (MNHN-IU-2014-17266) . – Stn CP1091, 15°10.24’S, 167°13.01’E, 344-350 m, 6.X.1994, 1 ov. ♀ 4.9 mm (MNHN-IU-2014-17267) . – Stn DW1097, 15°05.13’S, 167°10.76’E, 281-288 m, 7.X.1994, 1 ♀ 4.5 mm

(MNHN-IU-2014-17268). – Stn DW1106, 15°05.27’S, 167°11.88’E, 305-314 m, 7.X.1994, 1 ov. ♀ 4.9 mm (MNHN-IU-2014-17269) . – Stn CP1137, 15°41.52’S, 167°02.67’E, 360-371 m, 11.X.1994, 1 ov. ♀ 5.3 mm (MNHN-IU-2014-17270) . SANTO Stn AT01, 15°32.4’S, 167°16.4’E, 167-367 m, 14. IX.2006, 1 ♂ 4.5 mm (MNHN-IU-2014-17271) . – AT08, 15°40.5’S, 167°01.5’E, 366-389 m, 17.IX.2006, 1 ♂ 4.5 mm (MNHN-IU-2014-17272) . BOA1 Stn CP2479, 16°45’S, 167°52’E, 350-358 m, 15.IX.2005, 1 ♀ 4.5 mm (MNHN-IU-2014-17273) .

DISTRIBUTION„ Previously known from New South Wales, Queensland, Tasman Sea, Formosa Strait and Japan, in 64-419 m, and now from the Solomon Islands, Chesterfield Islands, Vanuatu, Loyalty Islands, New Caledonia, Norfolk Ridge and Hunter-Matthew, in 167- 780 m.

SIZE„ Males, 2.8-6.1 mm; females, 2.4-7.2 mm; ovigerous females from 3.3 mm.

DESCRIPTION„ Small to medium-sized species. Usually small but often exceeding 5.0 mm and attaining 7.2 mm.

Carapace: As long as broad; greatest breadth 1.2-1.3 × distance between anterolateral spines. Dorsal surface smooth, unarmed, somewhat convex in profile, anteriorly gradually lowered toward rostral dorsal concavity. Lateral margins moderately convex on branchial region; anterolateral spine small, directed anteroventrally, barely overreaching smaller lateral orbital spine, followed by larger spine at ordinary end of cervical groove (or anterior end of branchial region), and often followed by 1 or 2 small or obsolescent spines on branchial margin. Rostrum broad triangular, with interior angle of 42-53°, distally sharp; breadth fully two-thirds carapace breadth measured at posterior carapace margin; dorsal surface deeply concave. Lateral orbital spine somewhat anterior to level of anterolateral spine. Pterygostomian flap anteriorly angular, ending in small spine; no spine on surface.

Sternum: Excavated sternum anteriorly produced to spine, having longitudinal ridge in midline (often obsolete). Sternal plastron as long as broad, lateral extremities slightly convexly divergent posteriorly. Sternite 3 strongly depressed, anterior margin deeply excavated, with pair of submedian spines slightly separated from or close to each other, and often incurved, anterolateral angle rounded. Sternite 4 long relative to breadth; anterolateral margins gently divergent, very much longer than posterolateral margin. Anterolateral margin of sternite 5 anteriorly rounded, slightly more than half length of anterolateral margin of, and much longer than posterolateral margin of, sternite 4.

Abdomen: Smooth and glabrous. Somite 1 without transverse ridge. Somite 2 tergite 2.5-2.8 × broader than long, pleural lateral margins barely or feebly concave and strongly divergent posteriorly, ending in blunt tip. Pleuron of somite 3 with rounded lateral end. Telson three-quarters as long as broad; posterior plate semi-elliptical or semicircular, somewhat narrowed posteriorly, not emarginate on posterior margin, length subequal to greatest breadth, twice that of anterior plate.

Eye: Very elongate, slightly falling short of apex of rostrum, broadened distally, mesial margin convex. Cornea inflated, less than half length of remaining ocular peduncle.

Antennule and antenna: Ultimate article of antennule about twice as long as high. Antennal peduncle slender, barely reaching tip of eye. Article 2 with very small distolateral spine. Antennal scale usually slightly falling short of, rarely reaching distal end of article 5, slightly broader than article 5. Article 5 with distinct distomesial spine, length 2.5-3.0 × that of article 4, breadth about half height of ultimate antennular article. Flagellum of 17-24 segments not reaching distal end of P1 merus.

Mxp: Mxp1 with bases nearly contiguous. Mxp3 basis with 3 denticles obscured by stiff setae on well convex mesial ridge. Ischium with 16-23 denticles on crista dentata, flexor margin not rounded distally. Merus twice as long as ischium, well ridged along distal two-thirds of flexor margin but not ridged on proximal third, distolateral spine very small, often obsolete. Carpus with obsolescent distolateral spine and very small spine on proximal part of extensor margin.

P1: With long setae on distal portion, nearly glabrous elsewhere; more or less massive in males, slender in females; length up to 7 × longer than carapace; small tubercles on ventral surface, on merus and carpus in particular, irrespective of sex, but often absent, also occasionally present on palm. Ischium with small dorsal spine, without subterminal spine on ventromesial margin. Merus 1.4-1.5 × longer than carapace. Carpus 1.4-1.5 × longer than merus, dorsally with 1 median spine at anterior end. Palm 3.1-5.3 × (males), 3.9-5.0 × (females) longer than broad, slightly shorter than or subequal to carpus. Fingers distally incurved, crossing, occasionally gaping in large males (with rounded process at midlength of gaping opposable margin of movable finger), movable finger half as long as palm.

P2-4: Slender, moderately compressed; with sparse long setae. Meri successively shorter posteriorly (P3 merus 0.9 × length of P2 merus, P4 merus 0.9 × length of P3 merus), equally broad on P2-4 or very slightly narrower on P2 than on P3; length-breadth ratio, 5.6-6.5 on P2, 5.3-6.2 on P3, 4.5-5.3 on P4; unarmed; P2 merus as long as, occasionally slightly shorter than carapace, 1.6-1.7 × longer than P2 propodus; P3 merus 1.3 × length of P3 propodus; 4 merus 1.0-1.1 × length of P4 propodus. Carpi subequal, 1.3-1.6 × longer than dactyli on P2-4, 0.6 × length of propodus on P2 and P3, 0.5-0.6 × on P4. Propodi successively longer posteriorly; length-breadth ratio, 5.0 on P2-4; flexor margin with pair of distal spines preceded by row of spines along entire length at least on P2 and P3. Dactyli 0.4 × length of propodi on P2-4; curving at proximal third, ending in elongate subtriangular spine preceded by similar but successively diminishing spines, 7 or 8 in number, on flexor margin.

Eggs. Number of eggs carried, 3-30; small eggs (25 in number), 1.03 mm × 1.30 mm - 1.03 × 1.44 mm; large eggs (4 in number) ready to hatch, 1.69 mm × 1.55 mm.

COLOR„ The coloration of a specimen from Vanuatu was shown in Poore et al. (2011: pl. 6, fig. A). A female 4.5 mm, taken at SANTO Stn AT1, Vanuatu (MNHN-IU-2014-17271): pale pink overall, abdominal pleura and tailfan translucent.

REMARKS„ This is one of the most common species in the southwestern Pacific.

The carapace spination, broad rostrum, elongate eyes, and the shapes of antenna, Mxp3, and P2-4 are very similar in U. alcocki , U. cavirostris Alcock & Anderson, 1899 , U. latirostris Yokoya, 1933 , U. yokoyai Ahyong & Poore, 2004 and U. mauritius Baba, 2005 . However, this species is readily distinguished from the congeners except U. mauritius by the sternite 3 that bears a pair of distinct submedian spines rather than being unarmed on the anterior margin. This character suggests that the material reported under U. cavirostris by Van Dam (1933) from the Kai Islands is likely referable to U. alcocki . Uroptychus alcocki differs from U. mauritius in having the epigastric region smooth instead of bearing a pair of distinct ridges.

Examination of the material reported under U. brevirostris (ZLKU 4882) from the Ryukyu Islands by Baba (1973) discloses that it should be referred to U. alcocki . The specimen has a broad rostrum that is much wider than half the breadth of the carapace measured along the posterior margin and a pair of spines on the anterior margin of sternite 3, both characteristic of U. alcocki .

The material reported under U. cavirostris from the western Indian Ocean ( Tirmizi 1964) is an undescribed species, bearing no distinct spine on the anterior branchial margin, the character confirmed by examination of the material now in the Natural History Museum, London (BMNH 1966.2.3.27-40).

Figures

FIGURE 9 Uroptychus alcocki Ahyong & Poore,2003;A-E, G, I, J, male 4.5 mm (MNHN-IU-2014-17211);F, male 4.8 mm (MNHN-IU-2014-17251); H,male 4.3 mm (MNHN-IU-2014-17200).A, carapace and anterior part of abdomen,proximal part of left P1 included,dorsal.B,same, lateral.C,anterior part of sternal plastron.D,left antenna,ventral.E, left Mxp3,lateral.F, right Mxp3,lateral.G, left P1,mesial.H, same, dorsal. I, right P2,lateral. J, same, distal part, lateral. Scale bars: 1 mm.