Nephropsis suhmi Bate, 1888

Chang, Su-Ching & Chan, Tin-Yam, 2019, On the clawed lobsters of the genus Nephropsis Wood-Mason, 1872 recently collected from deep-sea cruises off Taiwan and the South China Sea (Crustacea, Decapoda, Nephropidae), ZooKeys 833, pp. 41-58 : 41

Nephropsis suhmi Bate, 1888 Figs 2E, F, 8

Nephropsis suhmi Bate, 1888: 181, pl. 23-fig. 3, pl. 24-fig. 2 (type locality: Aru Islands, Indonesia); Macpherson 1990: 306, figs 5b, 7d-f, 8c, d, 16b; 1993: 64; Holthuis 1991: 46, figs 60b, 82; Griffin and Stoddart 1995: 234; Poore 2004: 166, fig. 43e; Zarenkov 2006: 93; Chan 2010: 157; Yaldwyn and Webber 2011: 198.

Nephropsis meteor Zarenkov, 2006: 90, figs 12-14 (type locality: Gulf of Aden).

Material examined.

TAIWAN 2002, stn CP189, 21°39.91'N, 118°20.94'E, 1649-1629 m, 27 Aug 2002, 1 female cl 26.6 mm (NTOU M02131). TAIWAN 2004, stn CD238, 25°12.28'N, 123°1.85'E, 1689-1650 m, 23 Jul 2004, 1 male cl 17.8 mm (NTOU M02132). TAIWAN 2005, stn CP278, 24°23.63'N, 122°14.13'E, 1222-1239 m, 14 Jun 2005, 1 female cl 17.9 mm (NTOU M02133); stn OCP280, 24°23.71'N, 122°14.22'E, 1213-1261 m, 14 Jun 2005, 1 female 32.4 mm, 1 male cl 28.1 mm (NTOU M02134). TAIWAN 2006, stn CP372, 24°23.619'N, 122°14.138'E, 1220-1280 m, 26 Aug 2006, 1 female cl 12.9 mm (NTOU M02135). NanHai 2014, stn CP4106, 10°19.1500'N, 114°14.2530'E, 1292-1321 m, 6 Jan 2014, 1 female cl 18.5 mm (NTOU M02136); stn CP4108, 10°23.3701'N, 114°23.2672'E, 1707-1799 m, 6 Jan 2014, 1 female cl 35.7 mm (NTOU M02137), 1 male cl 38.3 mm (NTOU M02138), 1 male cl 34.8 mm (NTOU M02139). Dongsha 2014, stn CP4122, 21°34.976'N, 118°14.2792'E, 1713-1624 m, 30 Apr 2014, 1 female cl 40.4 mm (NTOU M02140). - Zhongsha 2015, stn CP4134, 19°55.837'N, 116°25.368'E, 1128-1278 m, 22 Jul 2015, 1 female cl 16.8 mm, 1 male cl 16.7 mm (NTOU M02141); stn CP4141, 18°54.31'N, 113°58.27'E, 1151-1286 m, 24 Jul 2015, 1 female cl 16.1 mm (NTOU M02142); stn CP4157, 19°52.593'N, 116°27.145'E, 1205-1389 m, 29 Jul 2015, 1 female cl 28.8 mm, 2 males cl 12.7, 16.0 mm (NTOU M02143); stn CP4163, 21°38.534'N, 118°19.179'E, 1683-1643 m, 31 Jul 2015, 1 female cl 46.8 mm (NTOU M02144); 1 female cl 39.4 mm, 1 male cl 19.9 mm (NTOU M02145); stn CP4167, 22°6.125'N, 119°7.775'E, 1756-1306 m, 1 Aug 2015, 1 male cl 13.2 mm (NTOU M02146). Cold Seep Cruise 2016, stn CST 11, 22°8.830'N, 119°15.681'E, 1319-1176 m, 27 Apr 2016, 1 female with damaged carapace (NTOU M02147); stn CST 17, 22°3.791'N, 118°58.804'E, 1483 m, 1 May 2016, 1 male cl 16.0 mm (NTOU M02148). Dongsha, 1256 m, 25 Apr 1996, 1 male cl 23.1mm (NTOU M02149).

Diagnosis.

Carapace covered with numerous granules of varying sizes (more developed in adults). Rostrum 0.4-0.6 times carapace length (somewhat longer in smaller specimens), bearing two (rarely three) lateral spines on each side, sometimes with one additional spine. Median groove reaching or almost reaching distal pair of lateral rostral spines. Each subdorsal carina with 0-7 (usually 3-5) spines and some granules. Gastric tubercle closer to supraorbital spine than to postcervical groove. Supraorbital spine well developed. Post-supraorbital spine present, usually followed by 1-2 spines. Postcervical groove deep, crossing dorsal midline. Distance between orbital border and postcervical groove 1.5-1.9 times distance between postcervical groove and posterior border of carapace.

Abdomen covered with granules. Tergites I–V each with distinct transverse groove interrupted medially. Pleura II–V slightly convex, each terminating in long, acute point which occasionally absent on pleuron V. Anterior border of pleura II and III usually bearing one strong spine (sometimes two) and some additional spinules. Anterior border of pleuron IV sometimes with a spine as well. Posterobasal border of pleuron V usually unarmed but occasionally bearing a single large spine. Dorsal surface of tail fan granulate; uropodal exopod lacking diaeresis.

Cheliped I bearing numerous granules; carpus with well-developed anterodorsal spine; outer surface bearing several spines (sometimes only 1-2 distinct spines in smaller specimens); inner surface with anteroventral spine and 1-2 (rarely 0) spines medially; dorsal surface of merus lined with spines. Carpus of pereiopod II 0.6-0.9 times palm length. Carpus of pereiopod III slightly more than half palm length. Dactyli of pereiopods IV and V approximately half propodus length.

Color in life.

Entire body vermilion red, except tips of large chelae, eyes, most dorsal parts of abdominal tergites I to V, and basal parts of antennular peduncles whitish.

Distribution.

Widely distributed in the Indo-West Pacific and recorded from Madagascar, Gulf of Aden, Maldive Sea, Arabian Sea, Indonesia, Australia, New Caledonia, western Tasman Sea, New Zealand, at 786-2029 m deep ( Macpherson 1990, 1993; Griffin and Stoddart 1995; Poore 2004; Zarenkov 2006; Yaldwyn and Webber 2011). This species is reported for the first time from Taiwan and the South China Sea (including Dongsha).

Remarks.

N. suhmi from the Indo-West Pacific and N. agassizii A. Milne-Edwards, 1880 from the West Atlantic ( Macpherson 1990; Alves-Júnior et al. 2016) are the only two known species of Nephropsis lacking a diaeresis on uropodal exopods. The present material fits well with the concept of N. suhmi in having the dactylus of pereiopod V approximately half the propodus length (vs. distinctly less than half in N. agassizii ; Holthuis 1974: fig. 19; Macpherson 1990: fig. 7c; Alves-Júnior et al. 2016: fig. 1A). The only discrepancy may be that in two (female of NTOU M02134; NTOU M02138) of the present 24 specimens there is a large posterior spine at the base of the pleuron V (Fig. 8C).

Nephropsis meteor Zarenkov, 2006 is closely related to N. suhmi and was described based on a single specimen from the Gulf of Aden ( Zarenkov 2006). The characters separating N. meteor from N. suhmi are the merus of large cheliped with two instead of one rows of spines, the postcervical groove dorsally armed with a pair of dorsal spines (vs. no dorsal spines), and the anterior margin of abdominal pleura III–V each bearing two spines instead of one spine ( Zarenkov 2006: table 3). However, in the original description and illustration of N. meteor ( Zarenkov 2006: 90, fig. 13B), the anterior margins of pleura IV and V each bearing only one and not two spines as listed in the table of distinguishing characters given by Zarenkov (2006: table 3). In the present material, there are 0-2 distinct spines on the anterior margin of each of the abdominal pleura III–V. The spination on the postcervical groove and merus of large cheliped are also rather variable in the abundant material examined in this study (i.e., 1-2 rows of spines on the merus of the large cheliped and 0-2 distinct spines on the dorsal part of postcervical groove). Thus, N. meteor should be considered as a synonym of N. suhmi as stated by Chan (2010) until there is more evidence to support their separation.