[Crustacea • 2025] Caridina brevilineata, C. fontinalis, C. hepingensis, C. qiongzhongensis, ... • Integrative Taxonomy reveals the Caridina clinata Cai, Nguyen & Ng, 1999 Species Complex (Decapoda: Atyidae), with Descriptions of Eight New Species from Hainan Island, China

Caridina clinata Cai, Nguyen & Ng, 1999,
 Caridina wenchangensis sp. nov., C. qiongzhongensis sp. nov., C. huangi sp. nov., C. hepingensis sp. nov., C. fontinalis sp. nov., C. tunchengensis sp. nov., C. brevilineata sp. nov., & C. caii sp. nov.

in Hou, J. Zhang, B. Chen, Y. Zhang, W. Chen et Guo, 2025. 

DOI: doi.org/10.3897/zse.101.172207

Abstract

Integrative analyses revealed that Caridina clinata Cai, Nguyen & Ng, 1999 represents a species complex comprising nine sibling species distributed across Hainan Island (China) and Vietnam. Among these, C. clinata sensu stricto (the nominal species itself) occurs in both regions, C. haivanensis is endemic to Vietnam, and the seven newly described species are endemic to Hainan Island. Evidence showed that the C. clinata population reported by Cai (2014) from Wuzhishan was actually a new species, herein described as C. caii sp. nov. This study documents nine Caridina species from Hainan Island, including eight new species and one newly recorded species. The new species are: C. wenchangensis sp. nov., C. qiongzhongensis sp. nov., C. huangi sp. nov., C. hepingensis sp. nov., C. fontinalis sp. nov., C. tunchengensis sp. nov., C. brevilineata sp. nov., and C. caii sp. nov. Additionally, Caridina clinata is recorded for the first time from Ledong, Hainan, and is redescribed herein. For each species, we provide comprehensive morphological descriptions, illustrations, taxonomic notes, habitat parameters, and IUCN threat assessments. Furthermore, we clarify the phylogenetic relationships between the newly discovered species and their congeners.

Key Words: 16S, COI, Hainan Island, Integrative taxonomy, morphology, new species

Collection sites of Hainan Island and live colouration of 9 Caridina species.
Caridina clinata Cai, Nguyen & Ng, 1999, Caridina wenchangensis sp. nov., C. qiongzhongensis sp. nov., C. huangi sp. nov., C. hepingensis sp. nov., C. fontinalis sp. nov., C. tunchengensis sp. nov., C. brevilineata sp. nov., and C. caii sp. nov.

Caridina wenchangensis sp. nov., C. qiongzhongensis sp. nov., 

C. huangi sp. nov., C. hepingensis sp. nov., 

C. fontinalis sp. nov., C. tunchengensis sp. nov., 

C. brevilineata sp. nov., and C. caii sp. nov.

Habitats of Caridina species on Hainan Island.
A. C. clinata Cai et al., 1999; B. C. caii sp. nov.; C. C. wenchangensis sp. nov.; D. C. qiongzhongensis sp. nov.;
E. C. huangi sp. nov.; F. C. hepingensis sp. nov.; H. C. tunchengensis sp. nov.; I. C. brevilineata sp. nov.

 Junjie Hou, Jiping Zhang, Bing Chen, Yixuan Zhang, Wenjian Chen, Zhaoliang Guo. 2025. Integrative Taxonomy reveals the Caridina clinata Cai, Nguyen & Ng, 1999 Species Complex (Crustacea, Decapoda, Atyidae), with Descriptions of Eight New Species from Hainan Island, China. Zoosystematics and Evolution. 101(4): 2295-2336. DOI: doi.org/10.3897/zse.101.172207