Tenagopelta pacifica , Ng, Peter K. L. & Castro, Peter, 2016

Ng, Peter K. L. & Castro, Peter, 2016, Revision of the family Chasmocarcinidae Serène, 1964 (Crustacea, Brachyura, Goneplacoidea), Zootaxa 4209 (1), pp. 1-182: 79-82

publication ID

http://doi.org/10.11646/zootaxa.4209.1.1

publication LSID

lsid:zoobank.org:pub:849BAB5C-464A-4B4A-A586-5742411EDC01

persistent identifier

http://treatment.plazi.org/id/F16BFB33-FFED-FFAA-FF6A-FB52FB92FE4D

treatment provided by

Plazi

scientific name

Tenagopelta pacifica
status

n. sp.

Tenagopelta pacifica  n. sp.

( Figs. 17View FIGURE 17 A, B; 26F; 33G; 42I; 47A, B; 54F; 61E; 79A ‒E; 88C; 91G; 102)

Hephthopelta  sp.— Serène & Vadon 1981: 118, 119, 120, 123 [ Philippines] Hephthopelta cf. lugubris  — Komai et al. 2012: 149, fig. 7 [ Philippines].

Type material. Holotype male (11.0 × 12.8 mm) ( NMCR) [photographed], Philippines, Bohol Sea, Maribojoc Bay , 100‒300 m, P.K.L. Ng coll., 11.2003‒04.2004. 

Paratypes: 1 male (10.7 × 11.2 mm) (USNM 46387), 1 female (10.7 × 11.7 mm) (USNM 46386); 1 female (7.6 × 8.0 mm) ( USNM 46385View Materials), Philippines, South China Sea , near Luzon, Albatross, stn 5278.—PANGLAO 2004  : 1 female (ZRC 2015.218), Philippines, Balicasag I., P.K.L. Ng coll., 29.05.2004; 1 male (10.2 × 11.4 mm) ( ZRC 2015.212View Materials) [G1 drawn], Maribojoc Bay , 100‒300 m, P.K.L. Ng coll., 11.2003‒04.2004  ; 2 males, 2 females ( ZRC 2015.213View Materials), Maribojoc Bay , 100‒300 m, P.K.L. Ng coll., 11.2003‒04.2004.—PANGLAO 2005  : 1 female ( ZRC 2015.202View Materials), Philippines, Bohol / Sulu Sea, stn CP2363, 09°06.0’N, 123°25.0’E, 437–439 m, 26.05.2005GoogleMaps  ; 1 female ( ZRC 2015.201View Materials), Bohol Sea, off Balicasag I., stn CP2394, 09°29’N, 123°40'E, 470–566 m, 30.05.2005GoogleMaps  ; 1 female (8.2 × 9.3 mm) ( ZRC 2015.197View Materials), Bohol Sea, Maribojoc Bay , stn CP2395, 09°36.2’N, 123°43.8’E, 382–434 m, 31.05.2005GoogleMaps  ; 1 female (9.2 × 10.4 mm) ( ZRC 2015.187View Materials) [photographed], Bohol Sea, Maribojoc Bay , stn CP2397, 09°35’N, 123°42'E, 642–669 m, 31.05.2005GoogleMaps  ; 2 juveniles, 6 males, 9 females ( ZRC 2015.190View Materials), Bohol Sea, Maribojoc Bay , stn CP2407, 09°41’N, 123°48'E, 256–268 m, 01.06.2005GoogleMaps  ; 1 male, 1 ovigerous females, 2 females (QM, ex ZRC), Bohol Sea, Maribojoc Bay , stn CP2408, 09°43.5’N, 123°47.1’E, 121–137 m, 01.06.2005GoogleMaps  ; 1 male ( ZRC 2015.199View Materials), Bohol Sea, Maribojoc Bay , stn CP2409, 09°44.8’N, 123°44.8’E, 220–257 m, 01.06.2005GoogleMaps  ; 1 female (6.6 × 6.9 mm) ( ZRC 2015.200View Materials) [photographed], Bohol I., Cortes , stn T15, 09°41.2’N, 123°49.0’E, 180 m, 24.06.2004.GoogleMaps  AURORA 2007: 1 female (6.3 × 6.8 mm) (MNHN-IU-2014-12808 ZRC 2015.208View Materials) [photographed], northwestern Philippines, stn CP2656, 16°02.01’N  –16°01.7’N to 121°52.02’E –121°53.9’E, 262‒278 m, 20.05.2007; 1 juvenile (ZRC 2015.207), stn CP2666, 15°56.35’N –15°57.65’N to 121°43.67’E –121°45.31’E, 184‒199 m, 02.05.2007; 1 female (8.2 × 9.4 mm) (MNHN-IU-2014-12809, ex ZRC 2015.203), stn CP2667, 15°56.81’N –15°54.52’N, 121°46.97’E –121°46.44’E, 280‒292 m, 292 m, 21.05.2007; 1 male (10.5 × 11.8 mm), 1 female (8.4 × 9.3 mm) [photographed] (ZRC 2015.193), stn CP2717, 14°29.96’N –14°28.94’N to 121°41.67’E – 121°43.13’E, 311‒362 m, 29.05.2007; 9 males, 3 females, 3 ovigerous females (ZRC 2015.194), stn CP2717, 15°04.36’N –15°04.06’N to 121°42.75’E –121°41.06’E, 368‒484 m, 29.05.2007; 2 males (8.0 × 9.0 mm, 8.0 × 9.1 mm), 1 female (7.2 × 7.9 mm) (ZRC 2015.192), stn CP2715, 14°31.50’N –14°33.09’N to 121°42.14’E – 121°42.05’E, 244‒249 m, 29.05.2007; 2 males, 2 females (10.0 × 11.4 mm) [photographed] (ZRC 2015.219), stn CP2716, 14°32.14’N –14°30.41’N to 121°40.80’E –121°41.16’E, 298‒356 m, 29.05.2002; 2 females (ZRC 2015.204), stn CP2718, 14°29.93’N –16°28.63’N to 121°46.72’E –121°97.56’E, 200‒220 m, 29.05.2007; 3 males (MNHN-IU-2014-12810, ex ZRC 2015.206), stn CP2719, 14°27.84’N –14°26.47’N to 121°47.90’E –121°48.36’E, 155‒204 m, 29.05.2007; 6 males, 7 females (ZRC 2015.195), stn CP2720, 14°25.30’N –14°26.63’N to 121°47.70’E—121°46.68’E, 256‒301 m, 29.05.2007; 5 males, 9 females (ZRC 2015.191), stn CP2721, 14°24.03’N –14°26.26’N to 121°46.83’E—121°47.56’E, 340‒360 m, 29.05.2007; 3 males, 2 females, 2 ovigerous females (MNHN-IU-2014-12811, ex ZRC 2015.196), stn CP2722, 14°24.45’N –14°25.80’N to 121°47.90’E— 121°46.19’E, 291‒338 m, 29.05.2007; 1 female (ZRC 2015.205), stn CP2734, 15°56.41’N –15°56.98’N to 121°48.71’E –121°49.21’E, 453‒460 m, 01.06.2007; 1 male (ZRC 2015.188), stn CC2746, 15°58.78’N – 15°56.63’N to 121°46.44’E –121°44.85’E, 182‒220 m, 0 2.06.2007.

Other material examined. Philippines. Hakuho-maru : 1 female (CBM-ZC 8770), Sulu Sea, stn SA-2, 10°36.48’N, 121°31.56'E, 362‒372 m, S. Ohtsuka coll., 08.12.2002GoogleMaps  .—MUSORSTOM 1: 4 males, 3 females (MNHN-IU-2013-15775, ex MNHN B-10501), stn CP25, 14°02’N, 120°18’E, 191‒200 m, 22.03.1976.— MUSORSTOM 2: 2 males (MNHN-IU-2013-9054), stn CP21, 14°02’N, 120°17’E, 191‒192 m, 22.11.1980; 1 male, 1 female (MNHN-IU-2013-9055), stn CP69, 14°07’N, 120°03’E, 1800‒1950 m, 30.11.1980.— MUSORSTOM 3: 2 males, 2 females (MNHN-IU-2013-9052), 1 ovigerous female, stn CP99, 14°01’N, 120°18’E, 196‒204 m, 01.06.1985.— PANGLAO 2005: 2 young females (smaller 6.9 × 7.7 mm) ( ZRC 2015.198View Materials) [photographed], Bohol Sea, Maribojoc Bay , stn CP2332, 09°39’N, 123°46'E, 396–418 m, 22.05.2005GoogleMaps  ; 2 males, 1 female (all badly damaged) ( ZRC 2015.189View Materials) [photographed], Bohol Sea, off Pamilacan I., stn CP2348, 09°30’N, 123°52'E, 196–216 m, 24.05.2005GoogleMaps  ;

Indonesia. 2 males (larger 12.2 × 14.3 mm), 3 females (largest 10.7 × 13.1 mm) (MNHN-IU-2013-9053), CORINDON 1, Makassar Strait, stn 273, 01°56.0’S, 119°16.0’E, 220‒ 180 m, 0 7.11.1980.

Diagnosis. Carapace ( Figs. 17View FIGURE 17 A, B; 102) subtrapezoidal, globose, 1.0–1.2 wider than long, margins with short setae; front bilobed, with shallow median cleft; anterolateral margins arcuate, without distinct lobes or teeth. Posterior margin of epistome ( Fig. 26View FIGURE 26 F) with broad semicircular median lobe with deep median fissure, semicircular lateral margins. Eye peduncle ( Fig. 26View FIGURE 26 F) filling orbit, short, mobile; cornea reduced, pigmented. Third maxilliped ( Fig. 33View FIGURE 33 G) merus quadrate, ischium rectangular, about same length as merus. Chelipeds ( Figs. 17View FIGURE 17 A, B; 47A, B; 102) subequal in length, slightly dissimilar in females, heteromorphic in males; fingers of minor  chela ( Fig. 47View FIGURE 47 B) subcircular in cross-section, not distinctly laterally flattened, gently tapering to tip, scissor-like, cutting margins with distinct sharp teeth; major chela of males ( Fig. 47View FIGURE 47 A) with enlarged dactylar teeth. Ventral surface of cheliped merus with 3 large, conspicuous teeth (sometimes additional small teeth or large tubercles) on outer margin in both sexes ( Fig. 42View FIGURE 42 I). Outer surface of adult male major chela with prominent swelling on median surface adjacent to dactylus ( Fig. 102View FIGURE 102 B). Inner margin of cheliped carpus with long distal tooth ( Fig. 17View FIGURE 17 A, B). Inner margin of basis-ischium of adult major cheliped gently granuliform ( Fig. 17View FIGURE 17 A). Long setae along margins of fingers, distal portion of cheliped propodi, dactyli, propodi of ambulatory legs. Proportionally long ambulatory legs ( Fig. 17View FIGURE 17 A, B). Meri of ambulatory legs with microscopic granules. P5 dactylus slightly upcurved ( Figs. 17View FIGURE 17 B; 102A, C, D, F); merus 0.8 cl. Fused thoracic sternites 1, 2 ( Fig. 54View FIGURE 54 F) semicircular, broad, short; fused thoracic sternites 3, 4 broad ( Figs. 54View FIGURE 54 F; 88C; 91G). Male pleon ( Figs. 54View FIGURE 54 F; 61E) with proportionally short telson. Sterno-pleonal cavity deep, press-button for pleonal holding as small, short tubercle posterior to thoracic sternal suture 4/5 near edge of sterno-pleonal cavity. Male thoracic sternite 8 short, rectangular; “supplementary plate” long, subovate; structures separated by relatively wide gap with most of the penis exposed (e.g., Fig. 61View FIGURE 61 E). G1 ( Fig. 79View FIGURE 79 A ‒D) with stout basal part; distal two-thirds long, tapering, with short spinules; tip subtruncate. G2 ( Fig. 79View FIGURE 79 E) longer than G1, straight, distal segment slender, directed inwards. Somites of female pleon ( Fig. 88View FIGURE 88 C) with convex lateral margins; telson proportionally short. Sterno-pleonal cavity of female ( Fig. 91View FIGURE 91 G) deep. Vulvae widely separated on outer margins of cavity close to suture 5/6.

Colour. The carapace of adult specimens is white to light brown with white pereiopods in life ( Fig. 102View FIGURE 102 A ‒C). Younger specimens have carapaces that vary from light brown to bright pink ( Fig. 102View FIGURE 102 D ‒F), with smallest specimens possessing pink pereiopods as well ( Fig. 102View FIGURE 102 F).

Etymology. The epithet pacifica  denotes the distribution of the new species in the Pacific Ocean in contrast to the Indian Ocean distribution of its two congeners.

Remarks. Specimens reported as “ Hephthopelta  sp.” by Serène & Vadon (1981: 123) from the western Philippines are almost certainly Tenagopelta pacifica  n. sp. as we have material from MUSORSTOM 1 and 2 that were referred to this species. The specimens on hand (including USNM specimens from Philippines identified by M.J. Rathbun) are remarkably consistent in all the diagnostic characters, with all of them possessing three welldeveloped, sharp teeth or pointed tubercles on the ventral, outer margins of the cheliped merus. The swelling on the median outer surface of the major chela adjacent to dactylus is most prominent in large males (e.g., Fig. 102View FIGURE 102 B), being less distinct but still discernible in smaller ones.

Tenagopelta pacifica  n. sp. is close to T. potens (Davie & Richer de Forges, 2013)  from Papua New Guinea, northeastern Australia and New Caledonia in its carapace form and proportions of the ambulatory legs. The most effective way to separate them is by their G1 structures; in T. pacifica  n. sp., the distal two-thirds is elongated and relatively slender ( Fig. 79View FIGURE 79 A), whereas the distal half of the G1 is distinctly shorter and stouter ( Fig. 79View FIGURE 79 K –N) in T. potens  .

The specimens from the Makassar Straits in Indonesia (MNHN-IU-2013-9053) are referred to T. pacifica  at present as they best agree with this species. The G1 is slightly shorter but essentially similar and can easily be explained by variation. The swelling on the outer surface of the male major chela is relatively lower and less pronounced compared to similar sized specimens from Philippines but this may also be due to variation.

Distribution. Western Pacific Ocean ( Philippines, Indonesia). Depth: 100– 669 m.

NMCR

New Mexico State University

USNM

Smithsonian Institution, National Museum of Natural History

ZRC

Zoological Reference Collection, National University of Singapore

Kingdom

Animalia

Phylum

Arthropoda

Class

Malacostraca

Order

Decapoda

Family

Chasmocarcinidae

Genus

Tenagopelta

Loc

Tenagopelta pacifica

Ng, Peter K. L. & Castro, Peter 2016
2016
Loc

Hephthopelta

Komai 2012: 149
Serene 1981: 118
1981