Abstract
A faunistic and ecological survey was conducted to document the diversity of freshwater atyid shrimps of Dawanshan Island. Two species of Caridina that occur on this island were documented and discussed. One of these, Caridina tetrazonasp. nov. is described and illustrated as new to science. It can be easily distinguished from its congeners based on a combination of characters, which includes a short rostrum, the shape of the endopod of the male first pleopod, the segmental ratios of antennular peduncle and third maxilliped, the slender scaphocerite, and the absence of a median projection on the posterior margin. Live individuals of the new species display a unique coloration pattern with four dark blue transverse bands on the body, and can be easily recognized in the field. So far, despite considerable surveying efforts made on neighboring islands, this species has only been found from a small stream on Dawanshan Island, which suggests that it may have a very limited range, probably endemic to Dawanshan Island. Molecular characteristics of the mitochondrial cytochrome c oxidase subunit I (COI) demonstrate that this species shows sufficient interspecific divergence from its congeners, including C. serrata Stimpson, 1860, which was found in four streams on Dawanshan Island, and has been previously reported on the neighboring islands of Hong Kong, Dong’ao, Wailingding, and Guishan.
Highlights
In order to better understand the diversity of the freshwater atyid fauna in the Dawanshan Island, an intensive field survey was carried out in June 2017
The results show that there are two species of atyid shrimps, Caridina tetrazona sp. nov. and C. serrata Stimpson, 1860
Caridina tetrazona sp. nov. is most similar to C. serrata Stimpson, 1860 in the short rostrum, the shape of the endopod of the male first pleopod, and the similar-sized eggs. It can be distinguished from C. serrata by the length of the basal segment of the antennular peduncle which is as long as the combined length of 2nd and 3rd segments; length of penultimate segment of 3rd maxilliped as long as basal segment; the distal segment is distinctly shorter than the penultimate segment; the absence of a projection on the posterior margin of telson, and the slender scaphocerite (3.6–3.7 times as long as wide versus 3.0–3.2 times in C. serrata)
Summary
Collecting evidence-based information is the foundation for addressing urgent global challenges in biodiversity conservation and sustainable management of native species. The atyid fauna of Dawanshan Island has not been properly surveyed. In order to better understand the diversity of the freshwater atyid fauna in the Dawanshan Island, an intensive field survey was carried out in June 2017. The results show that there are two species of atyid shrimps, Caridina tetrazona sp. Dawanshan Island (21°55'19.69" – 21°57'21.46"N, 113°42'54.30" – 113°45'06.09"E) covers an area of 8175 km, and is situated in the south of the Wanshan Islands. It is about 29 km northwest from Macau, 33 km from Zhuhai City, and 56 km northeast from Hong Kong (Fig. 1). The new species could be potentially seriously threatened and should be regarded as an endangered species
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
