Molecular evidence and differences in gonopod morphology lead to the recognition of a new species of the freshwater crab genus Candidiopotamon Bott, 1967 (Crustacea, Brachyura, Potamidae) from eastern Taiwan Author Shih, Hsi-Te https://orcid.org/0000-0003-1317-8783 Department of Life Science and Global Change Biology Research Center, National Chung Hsing University, 250, Kuo Kuang Road, Taichung 402, Taiwan htshih@dragon.nchu.edu.tw Author Naruse, Tohru https://orcid.org/0000-0001-9212-5246 Tropical Biosphere Research Center, Iriomote Station, University of the Ryukyus, 870 Uehara, Taketomi, Okinawa 907 - 1541, Japan Author Schubart, Christoph D. Zoology & Evolution, University of Regensburg, 93040 Regensburg, Germany text ZooKeys 2023 2023-09-11 1179 169 196 http://dx.doi.org/10.3897/zookeys.1179.106718 journal article http://dx.doi.org/10.3897/zookeys.1179.106718 1313-2970-1179-169 D5B5FB43D49245CDB571017D1014ED6F 754A434D9C3D5D87966D81ED3B00D4E5 Genus Candidiopotamon Bott, 1967 Candidiopotamon Bott, 1967: 210; Bott 1970 : 189; Minei 1974 : 245; Dai 1999 : 154; Shy and Yu 1999 : 95; Ng et al. 2008 : 161; Sasaki 2019 : 11551; Shy et al. 2020 : 1. Type species. Potamon (Potamon) rathbuni De Man, 1914. Distribution. Taiwan and the Ryukyu Islands (Okinawa, Kumejima, and Tokashiki islands) of Japan. Remarks. The genus Candidiopotamon was erected by Bott (1967) with the type species, Potamon (Potamon) rathbuni De Man, 1914, and the genus was named from the type locality of the type species, Candidius-See (= Sun Moon Lake, Rihyuetan) in Nantou Co. (= County), central-western Taiwan. Candidiopotamon was placed in the family Sinopotamidae Bott, 1970, by Bott (1970) , but the Sinopotamidae was synonymized under the Potamidae by Yeo and Ng (2004) , and this has been supported by genetic data ( Shih et al. 2009 ). Following this study, there are now two species in Taiwan ( C. rathbuni in the west and C. penglai sp. nov. in the east) and three from the Ryukyu Islands of Japan ( C. okinawense in Okinawa Island, C. kumejimense in Kumejima Island, and C. tokashikense in Tokashiki Island). Candidiopotamon guangdongense Dai, 1999, claimed to be found in Guangdong, China, but this is a junior synonym of C. rathbuni and was based on incorrect locality labels ( Shih and Ng 2011 ; Ng et al. 2017 ; Shy et al. 2020 ).