Sinopotamon fukienense Dai & Chen, 1979

Wang, Ruxiao, Pan, Da, Chen, Hui, Zhu, Binqing & Sun, Hongying, 2022, Revision of two species of Sinopotamon Bott, 1967 (Crustacea, Brachyura, Potamidae) endemic to China: a new combination and a new synonym, ZooKeys 1112, pp. 179-197 : 179

Sinopotamon fukienense Dai & Chen, 1979

Figs 2 , 3

Sinopotamon fukienense Dai & Chen, 1979: 247, fig. 2(1)-(3); Dai 1999: 259, pl. 17 (7), fig. 136.

Sinopotamon wuyiensis Li, Lin, Cheng & Tang, 1985: 144, figs 1-6 [synonymy].

Material examined.

2 males, 23.2 × 29.0 mm, NNU11B-211121SF1; 22.0 × 27.6 mm, NNU 11B-211121SF2, Guadun , Wuyishan National Park, Fujian, coll. Caixin Liu, Kangqin Zhang, Ruxiao Wang & Hongying Sun, 21 November 2021 . 3 female, 17.5 × 22.3 mm, NNU 11B-211121SF3; 19.5 × 25.4 mm, NNU 11B-211121SF4; 20.5 × 26.1 mm, NNU 11B-211121SF5, same data as above . 1 male, 22.5 × 28.1 mm, NNU 11B-211217SF6, Guadun , Wuyishan National Park, Fujian, coll. Hui Chen, Yunlong Sun, Ruxiao Wang & Hongying Sun, 17 December 2021 . 2 males, 17.9 × 22.2 mm, NNU 11B-211217SF7; 17.6 × 22.3 mm, NNU 11B-211217SF8, Tongmuguan, Wuyishan National Park , Fujian, same data as above . 1 female, 16.8 × 21.0 mm, NNU 11B-211217SF9, same data as above . 4 females, 17.9 × 23.7 mm, NNU 11B-211121SF10, Dazhulan , Wuyishan National Park, Fujian, coll. Caixin Liu, Kangqin Zhang, Ruxiao Wang & Hongying Sun, 21 November 2021 . 3 females, 22.3 × 28.0 mm, NNU 11B-211215SF11; 17.0 × 21.2 mm, NNU 11B-211215SF12; 26.3 × 33.4 mm, NNU 11B-211215SF13, same data as above, 15 December 2021 . 2 males, 22.5 × 29.0 mm, NNU 11B-211219SF14; 21.3 × 27.2 mm, NNU 11B-211219SF15, Longdu , Wuyishan National Park, Fujian, coll. Hui Chen, Yunlong Sun, Ruxiao Wang & Hongying Sun, 19 December 2021 . 1 female, 21.8 × 27.7 mm, NNU 11B-211219SF16, same data as above . 1 male, 19.6 × 24.9 mm, NNU 11B-211218SF17, Qiaoxia , Wuyishan National Park, Fujian, coll. Hui Chen, Yunlong Sun, Ruxiao Wang & Hongying Sun, 18 December 2021 . 1 female, 17.9 × 22.8 mm, NNU 11B-211218SF18, same data as above . 1 female, 35.5 × 43.4 mm, NNU 11B-211218SF19, Jiangdun , Wuyishan National Park, Fujian, same data as above .

Distribution and habitat.

Jiangxi Province, and Minjiang basin in Fujian Province. The crabs were found under rocks in mountain streams.

Remarks.

Sinopotamon wuyiensis was considered a new species based on its distinct morphological characters in both male and female specimens, especially in the male specimen having a pair of vulvae on sternite 6, which is not seen in any known species of Sinopotamon . Unfortunately, the type material of S. wuyiensis , which was originally deposited in Fujian Research Institute of Parasite Disease, Fuzhou, Fujian Province, is now lost (Youzhu Cheng, pers. comm.). Therefore, to investigate the status and validity of S. wuyiensis , we conducted comprehensive collections in Tongmu Village but found no record of S. wuyiensis in the area. Instead, we collected 21 new specimens from 14 localities within the area (Fig. 1 ), all of which were identified as S. fukienense by morphological comparison (Figs 2 , 3 ). According to the original description of S. wuyiensis , apart from the unique male sternite 6, S. wuyiensis is identical with S. fukienense in most characters, including outer margin of external orbital angle lined with 5-7 granules (Fig. 2A ; cf. Dai and Chen 1979; Li et al. 1985; Dai 1999); anterolateral margin ~ 2 × as long as external orbital outer margin (Fig. 2A ; cf. Dai and Chen 1979; Li et al. 1985; Dai 1999); G1 terminal segment tapering, tip directed outwards (Fig. 2D ; cf. Dai and Chen 1979: fig. 2(1), (2); Li et al. 1985: figs 1, 2; Dai 1999: fig. 136(3), (4)), not reaching suture sternites 5/6 (Fig. 2D ; cf. Dai and Chen 1979: fig. 2(1), (2); Li et al. 1985: figs 1, 2; Dai 1999: fig. 136(3), (4)), subterminal segment to terminal segment ratio ~ 2.5 (Fig. 2D ; cf. Dai and Chen 1979; Li et al. 1985; Dai 1999); female pleon subovate, vulvae ovate (Fig. 3 ; cf. Dai and Chen 1979; Li et al. 1985: figs 5, 6; Dai 1999: fig. 136(7), (8)). Therefore, it is most likely that the holotype of S. wuyiensis is a rare gynandromorphic specimen (Youzhu Cheng, pers. comm.), rather than a representative of a new species. Therefore, S. wuyiensis is herein synonymized with S. fukienense .

Figures

Figure 1. Localities of the sampling sites for Huananpotamon koatenense and Sinopotamon fukienense in the Wuyishan National Park, Fujian.

Figure 2. Sinopotamon fukienense, male, 23.2 x 29.0 mm, NNU 11 B- 211121 SF 1 A dorsal overall view ventral B view of anterior thoracic sternum and pleon C frontal view D ventral view of sterno-pleonal cavity with right G 1 in situ (left G 1 removed). Scale bars: 1.0 cm.

Figure 3. Sinopotamon fukienense, female, 22.5 x 29.0 mm, NNU 11 B- 211219 SF 14 A ventral view of pleon B ventral view showing female vulvae. Scale bars: 1.0 cm.