Caridina jiangkou Cai & Ng, 2018, sp. nov.
Creators: name: Cai, Yixiong
name: Ng, Peter Kee Lin
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Atyidae
Caridina
Caridina jiangkou

description: Caridina jiangkou sp. nov.   
(Fig. 13)  
urn:lsid:zoobank.org:act: D89160FE-F0C5-4F99-80AB- 2F07FEDED2CB  
 Material examined: Holotype: male, cl 4.8 mm, IZCAS DE 5036, 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) 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) 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) 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) 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.  
© 2018 Academia Sinica, Taiwan  
© 2018 Academia Sinica, Taiwan  
First pereiopod (Fig. 13D) 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) 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) 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) 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) 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) reaching 0.4 endopod length; appendix interna slender, reaching to 0.67 appendix masculina length.  
Uropodal diaeresis (Fig. 13L) 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) (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) (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) (vs. absent; cf. Liang and Yan, 1986: fig. 2(2)).   
 Distribution: Guizhou Province (Baishui Cave), China.
description: Published as part of 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), pp. 1-33 in Zoological Studies 57 (27) on pages 17-19, DOI: 10.6620/ZS.2018.57-27, http://zenodo.org/record/13314991