Caridina jiangkou, Cai & Ng, 2018

Cai, Yixiong & Ng, Peter Kee Lin, 2018, Freshwater Shrimps from Karst Caves of Southern China, with Descriptions of Seven New Species and the Identity of Typhlocaridina linyunensis Li and Luo, 2001 (Crustacea: Decapoda: Caridea), Zoological Studies 57 (27), pp. 1-33 : 17-19

publication ID	https://doi.org/ 10.6620/ZS.2018.57-27
DOI	https://doi.org/10.5281/zenodo.12826768
persistent identifier	https://treatment.plazi.org/id/03998788-FF8C-0402-C9D0-FED73E50F8C2
treatment provided by	Felipe
scientific name	Caridina jiangkou
status	sp. nov.

Treatment

Caridina jiangkou View in CoL sp. nov.

( Fig. 13 View Fig )

urn:lsid:zoobank.org:act:D89160FE-F0C5-4F99-80AB-2F07FEDED2CB

Material examined: Holotype: male, cl 4.8 mm, IZCAS DE 5036 View Materials , Baishui Cave in Jiangkou County , Guizhou Province, China, coll. zoological survey team, 15 May 1988 . Paratypes: 1 female, cl 4.0 mm, IZCAS DE 5037, 1 female, cl 6.6 mm, IZCAS DE 5038, data same as holotype; 2 males, 4.7-4.9 mm, 4 females, cl 3.5-6.2 mm, ZRC 2018.0484, same data as holotype; 1 male, cl 3.9 mm, 2 females, 4.2-5.8 mm, RMNH.CRUS. D.57292, data same as holotype.

Comparative material examined: Caridina guizhouensis Liang and Yan, 1986 - Holotype: male, cl 3.4 mm, SFU 84-73-1, Maopo Village, Yuping County, Guizhou Province, China, 84-73- 3. Paratype: 1 ovigerous female, SFU, cl 4.6 mm, eggs 0.95 × 0.60 mm, same data as holotype.

Description: Rostrum ( Fig. 13A View Fig View Fig View Fig ) short, straight, reaching to distal end of basal segment of antennular peduncle rostral formula 0-5+4-7/1- 5. Antennal spine fused with suborbital angle. Pterygostomian angle broadly rounded.

Sixth abdominal somite 1.8 times as long as fifth abdominal somite, about half carapace length, shorter than telson. Telson ( Fig. 13B, M View Fig ) with prominent posteromedian projection, posterior margin rounded, lateral pair of spines longer than intermediate pairs of spiniform setae, sub-lateral pairs shortest. Inner margin of lateral spines and surface of intermediate pairs of setae covered with spinules.

Eyes ( Fig. 13A View Fig ) well developed. Antennular peduncle about 0.7 times carapace length. Stylocerite reaching 0.75 basal segment length of antennular peduncle.

Mouthparts as figured. Mandible with blunt teeth at extremity of incisor process. Maxillula with simple palp, lower lacinia broadly rounded, upper lacinia broadly elongated, inner edge straight. Maxilla with slender palp, upper endite subdivided, scaphognathite tapering with numerous long setae posteriorly. Palp of first maxilliped stout, terminating in triangular prjection. Endopod of second maxilliped with fused dactylus and propodal segments. Third maxilliped ( Fig. 13C View Fig ) reaching to distal end of antennular peduncle, ending in single terminal claw; exopod reaching posterior quarter of penultimate segment, ultimate segment slightly shorter than pentultimate segment. Epipods on first 4 pereiopods.

First pereiopod ( Fig. 13D View Fig ) short, stout, reaching distal end of eyes, merus 2.1 times as long as broad; carpus strongly concave anteriorly, 1.2 times as long as high, chela 1.9 times as long as broad, fingers slightly shorter than palm. Second pereiopod ( Fig. 13E View Fig ) reaching beyond end of basal segment of antennular peduncle, carpus 4.0 times as long as high, chela shorter than carpus, 2.7 times as long as broad, fingers slightly shorter or as long as palm. Third pereiopod ( Fig. 13F, G View Fig ) reaching beyond distal end of antennular, propodus 10 times as long as broad, 3.7 times as long as dactylus (claw included); dactylus ending as 2 claws, with 8 spines. Fifth pereiopod ( Fig. 13H, I View Fig ) reaching to end of antennular peduncle, propodus 11 times as long as wide, 4.0 times as long as dactylus; dactylus with 36 spinules on flexor margin.

Endopod of male first pleopod ( Fig. 13J View Fig ) reaching to half of endopod length, sub-elliptical, 2.4 times as long as wide, appendix interna near distal end of endopod, reaching slightly beyond distal end of endopod. Appendix masculine of male second pleopod ( Fig. 13K View Fig ) reaching 0.4 endopod length; appendix interna slender, reaching to 0.67 appendix masculina length.

Uropodal diaeresis ( Fig. 13L View Fig View Fig View Fig ) with 13 spinules.

Habitat: Stream in a karst cave.

Etymology: Caridina jiangkou sp. nov. is named after the type locality Jiangkou County in Guizhou Province. The name is used as a noun in apposition.

Remarks: Caridina jiangkou sp. nov. resembles C. guizhouensis Liang and Yan, 1986 , in the form of the rostrum and telson. However, it can be easily separated from the latter by the form of the endopod of the male first pleopod (2.5 times as long as wide, Fig. 13J View Fig ) (vs. 3.0 times; cf. Liang and Zhou, 1993: fig. 2(7)); the longer appendix interna of the male second pereiopod (2/3 length of appendix masculine, Fig. 13K View Fig ) (vs. 1/3; cf. Liang and Yan, 1986: fig. 2(8)); and the presence of spinules on the surface of setae of the telson ( Fig. 13M View Fig ) (vs. absent; cf. Liang and Yan, 1986: fig. 2(2)).

Distribution: Guizhou Province (Baishui Cave), China.