Tubuca coarctata (H. Milne Edwards, 1852)

(Figs. 3A, B, 4A, B, 5)

Material examined. 1 male (CW 19.5 × CL 11.9 mm), NCHUZOOL 17189, Tai Tam Bay (22.24665°N, 114.22510°E), Hong Kong, coll. P. J. Jimenez, 29 Jun. 2022 .

Remarks. Tubuca coarctata is widely distributed in the West Pacific, from Indonesia (including Sumatra) to the Ryukyus and Fiji (Crane 1975; Shih et al. 2015). The type locality is listed as “ Odessa ” (H. Milne Edwards 1852: 156), which likely to be an error as the only familiar locality by that name is the port city of Odessa in Ukraine and, as such, the actual type locality is unknown (viz. Crane 1975). The male specimen collected from Hong Kong has the following important characters: carapace strongly trapezoid in outline, anterolateral angle acute, directed anterolaterally, anterolateral margin very short, dorsolateral margin moderately long (Fig. 5A); major cheliped with both outer dactylus and outer pollex with 1 groove (Fig. 5B); G1 moderately long, slightly tapering distally; thumb extending beyond base of tube; pore wide, at end of a short chitinous tube, flanges absent; inner process spinous, close to tubular end of shaft (Fig. 5C–F); fresh-preserved color on anterior carapace pale and dark on posterior, cheliped orange (Figs. 3A, B, 4A, B). The above characters agree with specimens of T. coarctata from Taiwan (Shih et al. 2015) and can be confirmed as T. coarctata by morphology. The COI analysis also supports the species identity (Fig. 7A; see DNA analysis). This is a new record to the fiddler crab fauna of Hong Kong.