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).