Thalamita spinifera Borradaile, 1902

Huang, Yu-Hsuan & Shih, Hsi-Te, 2021, Chthonius rhodochelatus Hadzi 1933, Zoological Studies 60 (60), pp. 1-45 : 23-26

Thalamita spinifera Borradaile, 1902 ( Figs. 4B , 14 )

Thalamita exetastica var. spinifera Borradaile, 1902: 203 (type locality: Maldives).

Thalamita exetastica – Sakai 1935: 76, figs. 9, 10a, c ( Japan: Sagami Bay); Sakai 1939: 417, fig. 12 ( Japan: Sagami Bay); Sakai 1965a: 126, pl. 64(3) ( Japan: Sagami Bay); Stephenson 1976: 20 ( Japan). (not Thalamita exetastica Alcock, 1899 )

Thalamita spinifera – Stephenson and Rees 1967: 93, fig. 34 ( Philippines); Sakai 1976: 371, pl. 133(2) ( Japan: Sagami Bay); Stephenson 1976: 24 ( Japan: Sagami Bay); Moosa 1981: 148 ( Philippines); Cariaso and Garcia 1986: 235, fig. 41 ( Philippines); Dai and Xu 1991: 33, fig. 25 (Nansha Is.); Wee and Ng 1995: 116, fig. 65; Ng et al. 2008: 155 (list); Yang et al. 2008: 790 (list; Nansha Is.); Yang et al. 2012: 328, fig. 128, pl. 14(2) ( China; Nansha Is.); Sasaki 2019: 9271 (list).

Material examined: Taiwan: 1 ovig. female (12.6 × 9.0 mm) (NCHUZOOL 16531), Erzihliao Fishing Port, Kaohsiung, coll. YH Huang, 8 Jul. 2018.

Diagnosis: Carapace subhexagonal, 1.4 times broader than long, surface densely pilose, posterior margin slightly broader than frontal ( Fig. 14A ). All anterior carapace ridges and cardiac ridges paired, mesobranchial regions with 2 pairs of ridges ( Fig. 14A ). Front with 6 lobes, median 2 lobes lower than submedian, lateral lobes smallest and tooth-like. Supraorbital margins broad with 2 notches. Anterolateral margins with 5 teeth, tooth 1 with small subsidiary basal tooth ( Fig. 14A ). Basal antennal segment granulated. Chelipeds with surface granulated; merus with 3 spines on inner margin; carpus with spine on inner margin, 3 smaller spines on outer margin; palm with 5 spines on dorsal surface, outer distal spine small or reduced to a tubercle, outer surface with 3 granulated ridges. Propodus of P5 with spines on inner margin ( Fig. 14B ).

Coloration in life: Carapace, chelipeds and P2–P5

A 3 mm

B

gray.

Distribution: Hawaii; French Polynesia; New Caledonia; Australia (western); Indonesia (Banda); Guam; Philippines; Nansha Is.; Taiwan (Erzihliao Fishing Port, Kaohsiung; Fig. 1 : no. 7); Japan (incl. Ogasawara Is.; Ryukyus); China (incl. Hainan I.); Malaysia (Malay Peninsula); Thailand; India; Maldives; Red Sea; Seychelles; Mayotte I.; Madagascar ( Sasaki 2019; this study).

Ecological notes: Specimens were caught by trawling and collected from fishing port (this study). The habitats are 30–80 meters deep, with muddy, sandy or pebbly bottoms ( Sakai 1976).

Remarks: Thalamita spinifera Borradaile, 1902 is similar to Tha. exetastica Alcock, 1899 , with Tha. spinifera distributed widely in the Indo-West Pacific and Tha. exetastica distributed in the Indian Ocean and the South China Sea ( Sasaki 2019). The female specimen from Taiwan is consistent with Tha. spinifera by the spines on the inner margin of propodus of P5 ( Fig. 14B ; Yang et al. 2012: fig. 128e, pl. 14(2)) (vs. smooth in Tha. exetastica ; Alcock and McArdle 1900: pl. 47(2); Yang et al. 2012: fig. 104e, pl. 12(4)).

Figures

Fig. 4. Species of the family Portunidae. A, Thalamita gatavakensis Nobili, 1906, male (16.5 × 9.3 mm) (NTOU), Mao-ao, New Taipei City; B, Thalamita spinifera Borradaile, 1902, female (12.6 × 9.0 mm) (NCHUZOOL 16531), Erzihliao Fishing Port, Kaohsiung; C, Thalamitoides quadridens A. Milne-Edwards, 1869, male (25.4 × 13.3 mm) (NTOU), Sansiantai, Taitung; D, Thalamitoides tridens A. Milne-Edwards, 1869, female (16.1 × 8.2 mm) (NCHUZOOL 16520), Dongsha I.; E, Thranita cerasma (Wee & Ng, 1995), female (66.4 × 42.6 mm) (NCHUZOOL 16537), Dongsha I.; F, Thranita coeruleipes (Hombron & Jacquinot, 1846), male (59.7 × 40.5 mm) (NCHUZOOL 16507), Wanlitong, Kenting, Pingtung.

Fig. 14. Thalamita spinifera Borradaile, 1902, female (12.6 × 9.0 mm) (NCHUZOOL 16531). A, carapace; B, right P5 (dorsal view).

Fig. 1. Taiwan main island and adjacent islets, with the collection localities shown in gray circles (see Table 1).