Chthonius rhodochelatus Hadzi 1933 Author Huang, Yu-Hsuan Department of Life Science, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 402, Taiwan. E-mail: phasmida 1130 @ gmail. com (Huang) phasmida1130@gmail.com Author Shih, Hsi-Te Department of Life Science, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 402, Taiwan. E-mail: phasmida 1130 @ gmail. com (Huang) & Research Center for Global Change Biology, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 402, Taiwan. * Correspondence: E-mail: htshih @ dragon. nchu. edu. tw (Shih) phasmida1130@gmail.com text Zoological Studies 2021 2021-10-01 60 60 1 45 http://dx.doi.org/10.5281/zenodo.12824381 journal article 10.6620/ZS.2021.60-60 1810-522X PMC9168908 35774269 12825574 Thranita cerasma ( Wee & Ng, 1995 ) ( Figs. 4E , 17 ) Thalamita cerasma Wee & Ng, 1995: 62 , figs. 30–32 ( type locality: Singapore ); Ng et al. 2008: 154 (list). Thalamita cerasma rectifrons – Crosnier and Moosa 2002: 395 , figs. 6, 7A, C–F, H–J ( French Polynesia : Austral Is. and Society Is.). Thalamita cerasma cerasma – Naruse and Shokita 2003: 43 , figs. 2, 3 ( Japan : Ryukyus). Thranita cerasma – Evans 2018: 43 (list); Sasaki 2019: 9281 (list). Thranita cf. cerasma – Shih et al. 2020b: 36 (Dongsha I.). ? Thalamita cerasma – Takeda and Marumura 1997: 16 , fig. 1C, D ( Japan : Kii Peninsula: Shirahama: Tanabe Bay). Material examined : Taiwan : 1 male (44.5 × 28.9 mm ), 1 female (59.7 × 38.8 mm ) (NCHUZOOL 16509), Dongsha I. ( 20°42'26.3"N 116°43'16.3"E ), coll. YH Huang and CY Chi, 2 Nov. 2019 ; 1 female (35.1 × 24.8 mm ) (NCHUZOOL 16526), Dongsha I. ( 20°42'26.3"N 116°43'16.3"E ), coll. YH Huang and CY Chi, 23 Sep. 2019 ; 1 male (16.3 × 11.0 mm) (NCHUZOOL 16527), Dongsha I. ( 20°42'3.1"N 116°43'4.4"E ), coll. YH Huang and CY Chi, 16 Aug. 2019 ; 1 male (20.1 × 13.5 mm ) (NCHUZOOL 16528), Dongsha I. ( 20°42'23.1"N 116°43'37.7"E ), coll. YH Huang and K Chang, 5 Nov. 2019 ; 1 male (38.5 × 23.7 mm ), 1 female (26.8 × 17.5 mm ) (NCHUZOOL 16529), Dongsha I. ( 20°42'26.3"N 116°43'16.3"E ), coll. YH Huang and CY Chi, 3 Nov. 2019 ; 3 females (22.2– 66.4 × 14.4–42.6 mm ) (NCHUZOOL 16537), Dongsha I. ( 20°42'26.3"N 116°43'16.3"E ), coll. YH Huang and CY Chi, 25 Sep. 2019 . Diagnosis : Carapace subhexagonal, 1.5–1.6 times broader than long, with broadest between anterolateral tooth 3, surface smooth. Frontal, protogastric and epibranchial regions each with a pair of ridges; mesogastric and metagastric ridges unbroken; mesobranchial and cardiac ridges absent ( Fig. 17A ). Front with 6 lobes. Supraorbital margins with 2 notches, inner lobe arched ( Fig. 17A ). Inner infraorbital lobes ending at acute angle. Anterolateral margins with 5 teeth, first 3 teeth large, tooth 4 smaller than 5 ( Fig. 17A ). Basal antennal segment with 2–3 sharp spines. Chelipeds slightly unequal; merus with 3 sharp spines on inner margin, a spinule each on distal end of dorsal and ventral surfaces near articulation of carpus; carpus with granules on dorsal surface, 1 strong spine on inner margin, 3 smaller spines on outer margin; palm with 5 sharp spines on dorsal surface, outer surface with 1 ridge, inner surface smooth. P5 with merus having strong spine on inner margin, distal end with small spine; propodus with inner margin serrated. G1 stout, with distal part gradually curved ( Fig. 17B–E ). Coloration in life : Carapace and chelipeds bright orange; P2–P4 green, joints orange, dactylus white with 5 mm 1 mm 5 mm Fig. 16. Thalamitoides tridens A. Milne-Edwards, 1869 , male (14.9 × 7.4 mm). A, carapace; B, basal antennal segment; C, palm of left cheliped (outer view); D–E, right G1; D, dorsal view; E, ventral view. Fig. 17. Thranita cerasma ( Wee & Ng, 1995 ) , male (44.5 × 28.9 mm). A, carapace; B–E, right G1; B, C, dorsal view; D, E, ventral view. pink stripes; P5 with dactylus green, border orange ( Fig. 4E ). Distribution : French Polynesia ; Taiwan (Dongsha I.; Fig. 1 : no. 17); Japan (Ryukyus); Malaysia ; Singapore ( Sasaki 2019 ; this study). Ecological notes : The habitat is the shallow subtidal zone of coral reefs and seagrass beds. Adult specimens were collected from around the corals ( Porites ) in the shallow subtidal zone, and the juveniles were found on the seagrass beds. Remarks : Thranita cerasma ( Wee & Ng, 1995 ) is similar to Thr. rubridens ( Apel & Spiridonov, 1998 ) , with Thr. cerasma distributed in the Pacific Ocean ( Sasaki 2019 ) and Thr. rubridens restricted in the Arabian Gulf ( Apel and Spiridonov 1998 ). The specimens from Taiwan agree with Thr. cerasma by the following characters: (1) P2–P4 green with joints orange in Thr. cerasma ( Fig. 4E ; Naruse and Shokita 2003 : fig. 2a) (vs. P2–P4 uniformly orange with joints pink in Thr. rubridens ; Apel and Spiridonov 1998 : pl. 9); (2) G1 with distal part stout, tip with setae on lateral and mesial sides in Thr. cerasma ( Fig. 17B–E ; Wee and Ng 1995 : fig. 32C–E) (vs. distal part slender, tip with setae on lateral side in Thr. rubridens ; Apel and Spiridonov 1998 : figs. 79a–c, 80, 81); (3) basal antennal segment with elongated spines ( Wee and Ng 1995 : fig. 32F) (vs. with short spines in Thr. rubridens ; Apel and Spiridonov 1998 : fig. 78a). With regard to the specimens identified as Thr. cerasma in Takeda and Marumura (1997 : fig. 1C, D) with whole body orange and joints pink, which is similar to Thr. rubridens ( Apel and Spiridonov 1998 : pl. 9) and may not belong to Thr. cerasma .