Trapezia plana Ward, 1941

Sun, Yu-Li, Jiang, Wei & Sha, Zhong-Li, 2024, Shallow-water Trapezioidea (Decapoda: Brachyura) from the South China Sea, including two new records, and notes on Tetralia glaberrima Herbst, 1790, Zootaxa 5476 (1), pp. 393-423 : 412

Trapezia plana Ward, 1941

( Fig. 9A–B )

Trapezia plana Ward, 1941: 14 , fig. 28.—Serène 1968: 88.—Feinberg 1971: 66.— Castro 2002: 364 ( Philippines); 2009: 272 (New Guinea).— Castro et al. 2004: 42 (list).

Trapezia punctipes Castro, 1997a: 87 , figs. 4A–C, pl. 2 fig. D; 1999a: 53; 1999b: 112.

Material examined. Nansha Islands: Mischief Reef, 115°34.4’E 9°53.5’N, 10 m, coll. Shaobo Ma, Yuli Sun, Ziming Yuan, 10 May 2022, 1 pre-adult (3.42 × 2.79 mm), NS-MJ-2022-1750, in Pocillopora ( Pocilloporidae ).— Hainan Island, 10 m, coll. Yuli Sun, 12 March 2023, 1 pre-adult (4.53 × 3.89 mm), VX0304, 1 male (9.42 × 8.19 mm), VX0302, in Pocillopora ( Pocilloporidae ).

Geographical distribution. Eastern Indian and western Pacific oceans ( Castro et al. 2004).

Remarks. This is a new record of Trapeziidae for the South China Sea, and this is the first time that the juvenile of Trapezia plana has been photographed ( Fig. 9B , NS-MJ-2022-1750). The morphological characteristics and live coloration of the specimens studied here are identical to the description of Trapezia punctipes , which is the synonym of Tr. plana sensu Castro (1997) . In addition, although the morphological features of the juvenile are not distinct, its coloration is also consistent with the description of Tr. punctipes (light orange body, orange-red spots on the walking legs, blue-grey eyes). We compared the COI sequence of it with other species of Trapezia reported herein, thus confirming that it is unique ( Fig. 11 ; Table 3 ).

Figures

FIGURE 9. A, Trapezia plana Ward, 1941, male (9.42 × 8.19 mm) (VX0302), Hainan Island; B, Trapezia plana, pre-adult (3.42 × 2.79 mm) (NS-MJ-2022-1750), Nansha Islands, Mischief Reef; C, Trapezia rufopunctata Herbst, 1799, male (19.18 × 18.18 mm) (NS-YS-2022-1098), Nansha Islands, Fiery Cross Reef; D, Trapezia septata Dana, 1852, female (12.63 × 10.51 mm) (NS-MJJ-2022-1050), Nansha Islands, Mischief Reef; E, Trapezia serènei Odinetz, 1983, male (5.36 × 4.78 mm) (XS-QL- 2022-1174), Xisha Islands, Seven Connected Islets.

FIGURE 11. Phylogenetic trees resolved by Bayesian analysis based on the sequences of COI. Nodal support values in the nodes correspond to Bayesian posterior probabilities (PP).