Two freshwater shrimp species of the genus Caridina (Decapoda, Caridea, Atyidae) from Dawanshan Island, Guangdong, China, with the description of a new species Author Chen, Qing-Hua South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510520, Guangdong Province, China Author Chen, Wen-Jian Department of Animal Science, School of Life Science and Engineering, Foshan University, Foshan 528231, Guangdong Province, China Author Zheng, Xiao-Zhuang Department of Animal Science, School of Life Science and Engineering, Foshan University, Foshan 528231, Guangdong Province, China Author Guo, Zhao-Liang Department of Animal Science, School of Life Science and Engineering, Foshan University, Foshan 528231, Guangdong Province, China zlguo@fosu.edu.cn text ZooKeys 2020 923 15 32 http://dx.doi.org/10.3897/zookeys.923.48593 journal article http://dx.doi.org/10.3897/zookeys.923.48593 1313-2970-923-15 138A88CCDF41437ABA1ACB93E3E36D62 4F0297887C89584A98A2AFB1F09D7817 Caridina serrata Stimpson, 1860 Figs 2B, C , 3B, C Caridina serrata Stimpson, 1860: 29 [type locality: Hong Kong, China]. Caridina serrata - Ortmann 1894 : 406; Bouvier 1905 : 76; 1925 : 258, fig. 593; Kemp 1918 : 289, fig. 12; Cai and Ng 1999 : 1605, figs 2, 3; Liang 2004 : 173, fig. 83; Chen et al. 2018 : 315, figs 2, 3. Material examined. 13 females, cl 3.5-6.8 mm, 2 ovigerous cl 3.7-5.6 mm, 5 males cl 3.0-5.8 mm, a small pool ( 21°56'48.6"N , 113°42'55.5"E , al. 5.4 m, stn 2), 27 June 2017, coll. Z. L. Guo, W. J. Chen; 17 females, cl 3.4-6.6 mm, 2 ovigerous females, cl 4.1-5.6 mm, 15 males, cl 2.9-5.5 mm, a small stream ( 21°56'43.6"N , 113°42'51.4"E , al. 27.2 m, stn 3), 27 June 2017, coll. Z. L. Guo, W. J. Chen; 5 females, cl 3.1-6.9 mm, 3 ovigerous, cl 3.5-5.8 mm, 3 males, cl 3.0-5.2 mm, a small stream ( 21°56'15.6"N , 113°43'33.4"E , al. 186.6 m, stn 4), 28 June 2017, coll. Z. L. Guo, W. J. Chen; 7 females, cl 3.4-6.9 mm, 4 males, cl 3.5-5.7 mm, a small stream ( 21°56'02.8"N , 113°43'29.0"E , al. 122.8 m, stn 5), 28 June 2017, coll. Z. L. Guo, W. J. Chen. Remarks. The present specimens are in agreement with the description and illustrations of Cai and Ng (1999) and Liang (2004) . Caridina serrata is highly adaptable and prolific, distributed everywhere on the Wanshan Islands, such as Dong'ao Island, Guishan Island, and Wailingding Island ( Chen et al. 2018 ). A close biogeographical connection of the atyid faunas among the Wanshan Islands is evident. This species is also distributed in Hong Kong ( Cai and Ng 1999 ), Chaqiao, and Zhongshan City ( Liang 2004 ). Ecological notes. Caridina serrata is commonly found in pools, streams, and artificial ditches on the island. Sometimes, the stream connects with the sea. Sediment at the site comprised sand, pebbles and gravel patches between large boulders. Hill streams are within secondary forests and are covered with aquatic plant (Fig. 2B, C ). The water parameters of the streams at the time of collection were: temperature 24-26 °C, pH 5.8-6.5, dissolved ammonia nitrogen 0.20-0.22 mgl-1, and dissolved oxygen 7.8-8.6 mgl-1; the water was clear and flowing. Caridina serrata is associated with dead leaves and aquatic plants, but also lives under pebbles and stones. The female carries fewer but large eggs (0.5-0.7 x 0.9-1.0 mm). The larvae go through direct development and hatch into benthic hatchlings that resemble miniature adults. Figure 2. Habitats of the two shrimp species in this study. A Habitat of Caridina tetrazona sp. nov. B, C habitat of C. serrata . Coloration. The live shrimp show light-red coloration and are translucent (Fig. 3B, C ). Distribution. Southern China (Hong Kong, Zhuhai City and Zhongshan City of Guangdong Province). Figure 3. Photos of live specimens of the two species of Caridina from Dawanshan Island. A Caridina tetrazona sp. nov. B dorsal view of C. serrata C lateral view of C. serrata .