Tenagopelta potens (Davie & Richer de Forges, 2013 ) Davie & Richer de Forges, 2013

Ng, Peter K. L. & Castro, Peter, 2016, Revision of the family Chasmocarcinidae Serène, 1964 (Crustacea, Brachyura, Goneplacoidea), Zootaxa 4209 (1), pp. 1-182 : 83-84

Tenagopelta potens (Davie & Richer de Forges, 2013) n. comb.

( Figs. 17 E–G; 26H; 33I; 47E–J; 54H; 61G; 79K–O)

Hephthopelta potens Davie & Richer de Forges, 2013: 795 , figs. 1–4 [type localilty: Australia, Queensland].

Type material. Holotype male (10.3 × 12.7 mm) (QM-W16974), Australia, Queensland, off Tully Heads, CSIRO, Soela , 17°59'02”S, 147°03'01"E, trawl, 260 m, 13.01.1986.

Paratypes: 1 female (6.2 × 7.1 mm) (QM-W17046), Australia, Queensland, off Babinda, 17°21'8”S, 146°48'5"E, epibenthic sled, 296–302 m, Franklin , 15.05.1986 .— CSIRO, Soela: 1 female (9.7 × 11.9 mm) (QM- W17047), Queensland, off Tully Heads , 17°59'09”S, 147°02'09"E, trawl, 250–252 m, 29.11.1985 ; 1 female (6.6 × 7.6 mm) (QM-W17048), Queensland, off Mission Beach , 17°54'03”S, 146°55'07"E, trawl, 212 m, 09.12.1985 ; 1 female (10.5 × 13.1 mm) (QM-W16999), Queensland, off Yeppoon , 22°56'01”S, 152°41'04"E, trawl, 225–282 m, 19.11.1985 ; 1 male (9.2 × 11.0 mm) (QM-W17049), Queensland, off Tully Heads , 18°07’S, 147°02'02"E, trawl, 220 m, 18.01.1986 ; 2 females (7.1 × 8.2 mm, 7.3 × 8.5 mm) (QM-W17050), Queensland, off Tully Heads , 18°02’S, 147°01'06"E, trawl, 220–222 m, 12.01.1986 ; 1 male (9.1 × 11.1 mm) (QM-W17051), Queensland, off Tully Heads , 18°01’S, 147°01'03"E, trawl, 224–228 m, 0 9.01.1986.

Other material examined. Papua New Guinea. BIOPAPUA: 1 female (MNHN-IU-2014-12812), South East Point , Gulf of Huon, stn CP3629, 06°57’S, 147°08’E, 240–269 m, 22.08.2010; 1 male (10.3 × 12.1 mm) , 1 female (11.3 × 13.1 mm) ( ZRC 2015.241 , ex MNHN-IU-2014-12813), Southeast Point, Gulf of Huon, stn CP3634, 07°29’S, 147°31’E, 279–290 m, 23.08.2010 ; 1 male (11.8 × 13.8 mm), 1 female (9.5 × 11.3 mm) (MNHN-IU- 2014-12814), 2 males (8.8 × 10.0 mm, 12.5 × 14.0 mm) ( ZRC 2015.242 ), Southeast Point, Gulf of Huon, stn CP3635, 07°29’S, 147°33’E, 280–302 m, 23.08.2010 ; 1 juvenile female (MNHN-IU-2014-12815), Open Bay , stn CP3664, 04°50’S, 151°38’E, 195–340 m, 23.09.2010 ; 1 female (MNHN-IU-2014-12816), Open Bay , stn CP3665, 04°50’S, 151°38’E, 225-340 m, 23.10.2010 ; 1 female (MNHN-IU-2014-12817), off Sepik River, stn CP3701, 03°57’S, 144°41’E, 198–219 m, 0 1.10.2010 . PAPUA NIUGINI 2012 : 1 female (MNHN-IU-2013-9014), Dampier Strait, Salomon Sea, stn CP4014, 05°35’S, 148°13'E, 630–870 m, 12.12.2012 ; 1 male (13.1 × 14.2 mm), 1 female (15.2 × 16.6 mm) (MNHN-IU-2013-9015), Astrolabe Bay , stn CP4028, 05°22’S, 145°47'E, 300–320 m, 14.12.2012 ; 1 male (MNHN-IU-2013-9158), N.Vanimo, Bismarck Sea, stn CP4062, 02°37’S, 141°18'E, 500–580 m, 21.12.2012.

Vanuatu. SANTO 2006 : 1 male (5.0 × 5.4 mm) ( ZRC 2015.186 ) [photographed], mislabeled station, waters outside Tutuba I., in excess of 100 m depth water, 18.10.2006.

New Caledonia. HALIPRO 1: 1 female (7.4 × 8.5 mm) (MNHN-IU-2013-9469), eastern New Caledonia , stn CP868, 21°14.539’S, 165°55.847’E, 430–450 m, 23.03.1994 ; 1 female (MNHN-IU-2013-9076), stn CP850, 21°43.6’S, 166°39.4’E, 541–580 m, 19.03.1994.— EXBODI: 2 females (MNHN-IU-2011-7302), Havannah Canal , stn CP3791, 22°15’S, 167°19’E, 750–863 m, 03.09.2011 ; 1 male, 1 female (MNHN-IU-2011-7512), Havannah Canal , stn CP3792, 22°18’S, 167°22’E, 850–876 m, 03.09.2011 ; 1 ovigerous female (MNHN-IU-2011-7378), Thio , stn CP3796, 21°32’S, 166°21’E, 434–455 m, 04.09.2011; 1 female (MNHN-IU-2013-1968) [photographed] , 1 female (MNHN-IU-2013-1969), Thio , stn CP3799, 21°33’S, 166°20’E, 461–466 m, 04.09.2011 ; 1 female (MNHN-IU-2011-7594), 1 female (MNHN-IU-2011-8190), Thio , stn CP3800, 21°32’S, 166°22'E, 279–282 m, 04.09.2011 ; 1 male (MNHN-IU-2011-7297), Toupeti , stn CP3808, 21°43’S, 166°39’E, 598–645 m, 05.09.2011 ; 4 females (MNHN-IU-2011-8560), Pass at Ounia, stn CP3826, 21°52’S, 166°51’E, 354–509 m, 07.09.2011 ; 1 male (MNHN-IU-2011-7755), Pass at Ounia, stn CP3827, 21°58’S, 166°57’E, 220–232 m, 08.09.2011 ; 1 female (MNHN-IU-2011-8474), large pass at Yaté , stn CP3837, 22°10’S, 167°15’E, 496–504 m, 09.09.2011 ; 1 male (MNHN-IU-2011-6498), large pass at Sarcelle , stn CP3842, 22°23’S, 167°22’E, 756–769 m, 10.09.2011 ; 1 male (MNHN-IU-2011-7885), 1 female (MNHN-IU-2011-8649), large pass at Sarcelle , stn CP3844, 22°20’S, 167°22’E, 815–970 m, 10.09.2011 .

Diagnosis. Carapace ( Fig. 17 E‒G) subtrapezoidal, globose, 1.1‒1.2 wider than long; dorsal, ventral surfaces, pereiopods covered by short tomentum, dorsal surface granular; front bilobed; anterolateral margins arcuate, granular, without distinct lobes or teeth. Eye peduncle ( Fig. 26 H) filling orbit, short, mobile, cornea reduced. Posterior margin of epistome ( Fig. 26 H) with broad semicircular median lobe with median fissure, semicircular lateral margins. Third maxilliped ( Fig. 33 I) merus subquadrate, ischium rectangular, slightly longer than merus. Proportionally long ambulatory legs ( Fig. 17 E‒G), folded P5 reaching beyond front, covered by tomentum; P5 merus 0.8 cl. Chelipeds ( Figs. 17 E‒G; 47E‒J) subequal in length, covered by short tomentum, slightly dissimilar in females, heteromorphic in males; fingers of minor chela ( Fig. 47 F, J) subcircular in cross-section, scissor-like, cutting margins with distinct teeth; major chela of males ( Fig. 47 E, I) with enlarged teeth. Outer surface of adult male major chela with prominent swelling on median surface adjacent to dactylus ( Fig. 47 G, H). Outer margin of ventral surface of cheliped merus with 3 large acute teeth. Inner margin of cheliped carpus with large pointed tooth ( Fig. 17 E–G). Fused thoracic sternites 1, 2 ( Fig. 54 H) semicircular, broad, long. Male pleon ( Figs. 54 H; 61G) with proportionally short telson. G1 ( Fig. 79 K‒N) stout, distal part relatively short, stout, curved inwards, with short spinules; tip truncate. G2 ( Fig. 79 O) longer than G1, curved, slender, distal segment long, curved. Female telson proportionally short. Vulvae relatively close together, located on steep outer margin of thoracic sternite 6 close to suture 5/6.

Remarks. Specimens from northern Queensland, Australia, are relatively smaller compared to other material from Papua New Guinea and New Caledonia, but all have a distinct swelling on the outer surface of the major male chela ( Fig. 47 G, H), usually visible even in medium-sized specimens. The smaller Papua New Guinea male specimens do not possess this swelling, with the outer surface of the chela gently convex ( Fig. 47 I), although large ones have a prominent granular swelling. The G1 structures of specimens from Papua New Guinea, Australia, Vanuatu, and New Caledonia are almost identical, and very similar to that figured by Davie & Richer de Forges (2013: fig. 4A, B), being stocky in form; although it seems slightly more slender and elongated in the Papua New Guinea material ( Fig. 79 K, L).

One small female (7.4 × 8.5, MNHN-IU-2013-9469) from New Caledonia is tentatively referred to T. potens . Its carapace is relatively broader than T. potens , with a shorter front and proportionately shorter ambulatory legs ( Fig. 17 G), but this may be because of its relatively small size.

Larger males (e.g., 11.8 × 13.8 mm, MNHN-IU-2014-12814) have a prominent swelling on the submedian part of the outer surface of the major palm, closer to the fingers. Smaller males (e.g., 10.3 × 12.1 mm, ZRC 2015.241) have the same area gently convex but not discernible as a swelling, whereas the outer surface of the palm of younger males (e.g., 8.8 × 10.0 mm, ZRC 2015.242) is evenly convex.

Tenagopelta potens is close to T. pacifica n. sp., and the differences have been discussed under the latter species.

Distribution. Western Pacific Ocean ( Papua New Guinea to New Caledonia, including Queensland, Australia). Depth: 195– 970 m.

Figures

FIGURE 17. Overall dorsal view of species of Tenagopelta n. gen. A, T. pacifica n. sp., Philippines: holotype male 10.3 × 11.9 mm (NMCR); B, T. pacifica n. sp., Philippines: female 9.2 × 10.4 mm (ZRC 2015.187); C, T. brachyphallus n. sp., Australia: holotype male 6.1 × 6.9 mm (NMV J 61680); D, T. brachyphallus n. sp., Australia: female 6.9 × 7.6 mm (NMV J 61680); E, T. potens, Papua New Guinea: male 10.3 × 12.1 mm (ZRC 2015.241); F, T. potens, Papua New Guinea: female 11.3 × 13.1 mm (ZRC 2015.241); G, T. potens, New Caledonia: female 7.4 × 8.5 mm (MNHN-IU- 2013 - 9469).

FIGURE 26. Frontal view of species of Statommatia n. gen. and Tenagopelta n. gen. A, Statommatia apta, Philippines: holotype 7.8 × 9.4 mm (USNM 46389); B, Statommatia apta, Philippines: male 5.9 × 7.1 mm (ZRC 2015.239); C, Statommatia malagasy n. sp., Madagascar: holotype male 9.9 × 12.4 mm (MNHN-IU- 2010 - 4370 a); D, Statommatia knudseni, New Caledonia: holotype male 4.7 × 6.9 mm (ZMUC CRU- 6974); E, Statommatia granulosa n. sp., New Caledonia: holotype male 4.1 × 4.7 mm (MNHN-IU- 2013 - 9454); F, Tenagopelta pacifica n. sp., Philippines: holotype male 10.3 × 11.9 mm (NMCR); G, Tenagopelta brachyphallus n. sp., Australia: holotype male 6.1 × 6.9 mm (NMV J 61680); H, Tenagopelta potens, Papua New Guinea: male 11.8 × 13.8 mm (MNHN-IU- 2011 - 1504).

FIGURE 33. Third maxilliped of species of Statommatia n. gen. and Tenagopelta n. gen. A, Statommatia apta, Philippines: holotype male 7.8 × 9.4 mm (USNM 46389); B, Statommatia apta, Philippines: male 5.9 × 7.1 mm (ZRC 2015.239); C, Statommatia knudseni, New Caledonia: holotype male 4.7 × 6.9 mm (ZMUC CRU- 6974); D, Statommatia pubescens, South China Sea: holotype male 5.0 × 7.9 mm (after Chen 1998: fig. 23 - 5); E, Statommatia malagasy n. sp., Madagascar: holotype male 9.9 × 12.4 mm (MNHN-IU- 2010 - 4370 a); F, Statommatia granulosa n. sp., New Caledonia: holotype male 4.1 × 4.7 mm (MNHN-IU- 2013 - 9454); G, Tenagopelta pacifica n. sp., Philippines: holotype male 10.3 × 11.9 mm (NMCR); H, Tenagopelta brachyphallus n. sp., Australia: holotype male 6.1 × 6.9 mm (NMV J 61680); I, Tenagopelta potens, Papua New Guinea: male 11.8 × 13.8 mm (MNHN-IU- 2011 - 1504).

FIGURE 47. Chelae of species of Tenagopelta n. gen. A, B, T. pacifica n. sp., Philippines: holotype male 10.3 × 11.9 mm (NMCR); C, D, T. brachyphallus n. sp., Australia: paratype male 6.9 × 7.6 mm (NMV J 54594); E ‒ H, T. potens, Papua New Guinea: male 11.8 × 13.8 mm (MNHN-IU- 2011 - 1504); I, J, T. potens, Papua New Guinea: male 8.8 × 10.0 mm (ZRC 2015.242).

FIGURE 54. Anterior thoracic sternum and male pleon of species of Statommatia n. gen. and Tenagopelta n. gen. A, Statommatia apta, Philippines: holotype 7.8 × 9.4 mm (USNM 46389); B, Statommatia apta, Philippines: male 5.9 × 7.1 mm (ZRC 2015.239); C, Statommatia malagasy n. sp., Madagascar: holotype male 9.9 × 12.4 mm (MNHN-IU- 2010 - 4370 a); D, E, Statommatia knudseni, New Caledonia: holotype male 4.7 × 6.9 mm (ZMUC CRU- 6974); F, Tenagopelta pacifica n. sp., Philippines: holotype male 10.3 × 11.9 mm (NMCR); G, Tenagopelta brachyphallus n. sp., Australia: holotype male 6.1 × 6.9 mm (NMV J 61680); H, Tenagopelta potens, Papua New Guinea: male 11.8 × 13.8 mm (MNHN-IU- 2011 - 1504).

FIGURE 79. Gonopods of species of Tenagopelta n. gen. A ‒ E, T. pacifica n. sp., Philippines: paratype male 10.2 × 11.4 mm (ZRC 2015.212); F ‒ J, T. brachyphallus n. sp., Australia: holotype male 6.1 × 6.9 mm (NMV J 61680); K ‒ N, T. potens, Papua New Guinea: male 11.8 × 13.8 mm (MNHN-IU- 2011 - 1504). A, F, K, ventral view of left G 1; B, G, L, dorsal view of left G 1; C, H, M, ventral view of distal part of left G 1; D, I, N, dorsal view of distal part of left G 1; E, J, O, left G 2. Scales: A, B, E, F, G, J, K, L, O = 0.5 mm; C, D, H, I, M, N = 0.1 mm.