Austruca perplexa (H. Milne Edwards, 1852 )

Shih, Hsi-Te, Wong, Kingsley J. H., Chan, Benny K. K., Nguyen, Thanh Son, Do, Van Tu, Ngo, Xuan Quang & Hsu, Pei-Yi, 2022, Branchipolynoe onnuriensis Kim & Choi & Eyun & Kim & Yu 2022, sp. nov., Zoological Studies 61 (66), pp. 1-24 : 9

Austruca perplexa (H. Milne Edwards, 1852) ( Fig. 3E, F )

Gelasimus perplexus H. Milne Edwards, 1852: 150 , pl. 4(18) (type locality: Java). Gelasimus annulipes – Kingsley 1880: 148 [part]. Gelasimus chlorophthalmus – Kingsley 1880: 151 [part]. Uca (Celuca) lactea perplexa – Crane 1975: 298, 300, 612, 613, figs.

18D–F, 19C–H, 26D, 31E, 54K, KK, 69C (part). Uca perplexa – Yamaguchi 1994: 165; S-L Yang et al. 2008: 807;

Shih et al. 2009: 376; Shih et al. 2013: 643. Uca perplesca – Do 2003: 8. Uca (Paraleptuca) perplexa – Ng et al. 2008: 241. Uca (Austruca) perplexa – Naderloo et al. 2010: 24, figs. 16a–g, 17a, b,

18c–f; Shih et al. 2016a: 62, fig. 2C–E.

Austruca perplexa – Shih et al. 2015: 189, figs. 152–156; Shih et al. 2016b: 153, 168, fig. 8F; Ng et al. 2017: 123; Sasaki 2019: 12436; Wada 2019: e142.

Austruca (Austruca) perplexa – Rosenberg 2019: 734.

Material examined: Binh Thuan: 14 òò (8.2–17.4 mm), 3 ññ (12.9–15.7 mm) (NCHUZOOL 15116), Nguyen Thong, Phu Hai, Phan Thiet, coll. I-H. Chen et al. 26 Nov. 2010. Ho Chi Minh: 6 òò (7.4– 10.3 mm), 1 ñ (7.0 mm) (NCHUZOOL 15117), 1 ò (9.8 mm), 1 ñ (7.1 mm) (NCHUZOOL 15118), Giong Ao, Can Thanh Town, Can Gio, coll. H.- T. Shih and P.-Y. Hsu, 13 Oct. 2017. Kien Giang: 4 òò (11.1–12.4 mm), 1 ñ (13.3 mm) (NCHUZOOL 15119), Phu Quoc Island, coll. H.- T. Shih, 2 Dec. 2012. Southern Vietnam: 2 òò (14.2, 18.7 mm) ( ZRC), coll. V. T. Nguyen, 2010.

Distribution: Nicobar Islands, Indonesia, Australia, New Caledonia, New Guinea, Philippines, Borneo, Malay Peninsula, Thailand, Cambodia, Vietnam, Taiwan and Ryukyus.

Remarks: Austruca perplexa is widely distributed in the IWP, from the western part of the eastern Indian Ocean to the West Pacific, including the Ryukyus (and probably in main islands of Japan) and Taiwan (including Penghu and Dongsha Island) in the East Asia. Recently, Shih and Poupin (2020) recognized a new allied species, A. citrus Shih & Poupin, 2020 , from Fiji and eastwards (see also Crane 1975; Shih et al. 2009; Naderloo et al. 2010; Trivedi et al. 2018; Shih and Poupin 2020). Austruca perplexa was often misidentified as A. annulipes and A. lactea (see Shih and Poupin 2020), but can be distinguished by the characters of the anterolateral angles, fingers in the male major cheliped and the G1 (see dichotomous key provided below in this study).

Figures

Fig. 3. Dorsal view of carapace and frontal view of major cheliped. Austruca annulipes (A, B, specimens not catalogued, Phu Quoc Island, Kien Giang); A. lactea (C, D, NCHUZOOL 15115, CW 13.1 mm, Nam Dinh); A. perplexa (E, F, NCHUZOOL 15117, CW 10.3 mm, Can Gio, Ho Chi Minh City); Gelasimus borealis (G, H, NCHUZOOL 15121, CW 21.1 mm, Dong Rui, Quang Ninh).