Uca acuta ( Stimpson, 1858 )

Shih, Hsi-Te, Ng, Peter K. L., Fang, Shou-Hua, Chan, Benny K. K. & Wong, Kingsley J. H., 2010, Diversity and distribution of fiddler crabs (Brachyura: Ocypodidae: Uca) from China, with new records from Hainan Island in the South China Sea, Zootaxa 2640, pp. 1-19 : 3-6

Uca acuta ( Stimpson, 1858)

( Fig. 2 A–D)

Gelasimus acutus Stimpson, 1858: 99 ; 1907: 105, pl. 14, fig. 3 [type locality Macao, off south coast of China]; Kingsley 1880: 144 [list].

Uca demani (not U. demani Ortmann, 1897 )— Gee 1926: 165 (part) [Xiamen]; Kellogg 1928: 356 [list].

Uca manii — Gee 1926: 165 [ Chin Bey].

Uca mani — Gordon 1931: 528 [list].

Uca arcuata (not Gelasimus arcuatus De Haan, 1835 )— Shen 1937a: 309 [North China].

Gelasimus manii — Shen 1940: 232 [ Hong Kong].

Gelasimus urvillei (not H. Milne Edwards, 1852)— Shen 1940: 232 [ Hong Kong].

Uca urvillei (not H. Milne Edwards, 1852)— Shen & Dai 1964: 112, unnumbered text-fig. [Guangdong]; Lai & He 1998: 172 [Guangxi].

Uca (Deltuca) acuta acuta — Crane 1975: 25, pl. 1E–H, fig. 61B [ Jiaozhou, Shandong; Fujian].

Uca acuta acuta — Yamaguchi 1994: 183 [ Jiaozhou, Shandong; Xiamen].

Uca acuta — Jones & Morton 1994: 12, pls. 1A, B, 2A, B, fig. 1 [ Hong Kong]; Yang et al. 2008: 807 [East China Sea; northern South China Sea].

Uca (Tubuca) acuta —Ng et al. 2008: 241 [list].

Material examined. Fujian: 2 3 (19.45, 24.26 mm) (MBMCAS 166374), Xiunpu, Quanzhou, coll. H.-L. Chen, 21 Jun. 1975; 10 3 (CW 11.03–22.61 mm), 5 ƤƤ (15.5–20.29 mm, one damaged) ( ZRC 2002.0563), Longhai, Xiamen, coll. P.K.L. Ng & S.-H. Fang, 22 Sep. 2002; 17 3 (16.71–20.45 mm), 10 ƤƤ (5 ovig.) (11.85–17.26 mm) (NCHUZOOL 13348), Jimei, Xiamen, coll. H.-T. Shih & J.-H. Lee, 1 Jul. 2004; 10 3 (12.4–25.84 mm), 4ƤƤ (11.19–20.3 mm) (MBMCAS 166385), Zhuta, Yunxiao, Zhangzhou, 3 Apr. 1985. Hong Kong: 1 3 (23.31 mm) (NCHUZOOL 13349), Tai O, coll. K.J.H. Wong & K.H. Lo, 28 Apr. 2009. Hainan: 8 3 (17.18–23.26 mm), 3 ovig. ƤƤ (15.96–16.85 mm) (NCHUZOOL 13351), Dongzhai, coll. H.- T. Shih & J.-H. Lee, 23 Jun. 2004.

Live coloration. Carapace dark brown, mottled with light yellow ( Fig. 2 A); or light brown ( Fig. 2 C). Eyestalk brownish green ( Fig. 2 A–C). Major chela with manus bright orange-red, fingers white ( Fig. 2 B).

Ambulatory legs black ( Fig. 2 A–C). Juvenile with carapace creamy white, especially antero-dorsally; legs bright orange ( Fig. 2 D).

Distribution. Continental China and Vietnam ( Table 1 ).

Remarks. The species is distributed from southern Shandong (Yellow Sea), along the coasts of Southeast and South China, to northern Vietnam ( Crane 1975; Dai et al. 1986; Dai & Yang 1991; Kosuge et al. 1997). Uca acuta prefers muddy habitats along the continental coast, habits similar to U. paradussumieri , but the two species do not occur in Taiwan (including Penghu Island) ( Crane 1975; Shih 1994; Ng et al. 2001; Shih et al. 2008).

Uca acuta is almost always sympatric with U. arcuata , and both species are also similar in coloration and general morphology ( Crane 1975; Jones & Morton 1994; Kosuge et al. 1997), although U. arcuata is generally larger. Crane (1975) reported the largest CW of the above two species as 37 mm and 22 mm, respectively (our largest specimen of U. acuta attained 25.84 mm CW). However, they are easily distinguished in the field by coloration and size in the field ( Fig. 2 A–F), and the tubercle size on the major palm ( Fig. 2 A, B, E, F). Preserved specimens can also be distinguished by the structure of the anterior and posterior flanges of the G1 (see key; Crane 1975: 625, fig. 61B, J; Jones & Morton 1994: 11, figs. 1, 2). During our collections, both species were collected from higher intertidal mudflats around mangroves, in Xiamen, Fujian and Dongzhai, northern Hainan Island. Due to their similarity, U. acuta has probably been confused and mixed with U. arcuata in earlier surveys from Southeast and South China, and older records of both species need be checked.

Uca coarctata *? Uca tetragonon * Uca typhoni * Uca vocans *? *

Figures

FIGURE 2. Photographs in life of Uca acuta (Stimpson, 1858) from Xiamen, Fujian, China (A – C, NCHUZOOL 13348; A, B, CW 18.92 mm; C, CW 17.26 mm; and D) and U. arcuata (De Haan, 1835) from Dongzhai, Hainan, China (E – F) (NCHUZOOL 13363, CW 33.84 mm). A, E, dorsal view of adult male; B, F, frontal view of adult male; C, dorsal view of adult female; D, juvenile.

Tables

TABLE 1. The records of Uca species in different province or area of China (cf. Fig. 1) and Vietnam, according to the distribution from north to south.?, record questioned, see Remarks under each species.

	Shandong	Jiangsu (including Shanghai)	Zhejiang	Fujian	Guangdong (including Hong Kong)	Guangxi	Hainan	Vietnam
Uca arcuata	*	*	*	*	*	*	*	*
Uca acuta	*			*	*	*	*	*
Uca paradussumieri		*	*	*	*	*	*	*
Uca lactea			*	*	*	*	*	*
Uca borealis				*	*	*	*	*
Uca crassipes				*	*		*
Uca triangularis					*
Uca dussumieri					*?
Uca annulipes							*