Caridina alu 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 alu

description: Caridina alu sp. nov.   
(Figs. 4-6)  
urn:lsid:zoobank.org:act: F7760EDF-36A2-48DD-9B49- 409B6B51A1CD  
 Material examined: Holotype: male, cl 6.5 mm, IZCAS DE 5029, caught by fish traps in subterranean river, Alu Cave, behind a hotel at Alufa Village, Luxi County, Yunnan Province, southern China, coll. Kos, B. Sket & Velkovrh. 24 Nov 1995. Paratypes: 1 female, cl 4.0 mm, IZCAS DE 5030, same data as holotype; 1 male, cl 6.0 mm, 1 female, cl 4.8 mm, RMNH.CRUS. D.57290; 1 male, cl 6.2 mm, 1 female, cl 5.6 mm, UL, same data as holotype; 2 males, cl 5.8-6.3 mm, 4 females, 3.0- 4.7 mm, cl 4.2-6.2 mm, ZRC 2018.0481, same data as holotype.   
 Comparative material examined: Caridina sphyrapoda Liang and Zhou, 1993 - holotype: male, cl 5.5 mm, SFU 85a-8-1, Longdong river, Laibing County, Guangxi Province, China, coll. J. Zhou, 24 May 1985. Paratype: 1 female, cl 3.8 mm, 1 ovigerous female, cl 5.8 mm, SFU 85a-8-2, same data as holotype. Others: 3 males, cl 4.5-6.3 mm, 6 females, cl 4.7-6.6 mm, IZCAS, stream near Kuiyang Town, Yinlin County, Guangxi Province, coll. Y. Cai, H. Tang and H. Zhen, Nov 1993.   
 Description: Rostrum long (Fig. 4A, B), straight, reaching slightly beyond distal end of scaphocerite, armed dorsally with 16-24 teeth, of which 5-8 are situated on carapace behind posterior margin of orbital margin, occupying about half carapace length, armed ventrally with 4-12 (mode 7-10) teeth. Orbit narrow; antennal spine sharp, completely fused with suborbital angle. Pterygostomian angle broadly rounded.   
Sixth abdominal somite twice as long as fifth abdominal somite, about half carapace length, slightly shorter than telson. Telson (Fig. 5G) without posteromedian projection, posterior margin rounded, lateral pair of spines longer than sub-lateral pairs, subequal to intermediate pairs of spines.  
Eyes degenerated (Fig. 4A, B), small, pigment at centre of cornea. Antennular peduncle (Fig. 5A) 0.54 times as long as carapace. Antennular flagellum extraordinary long, more than twice total length. Stylocerite reaching 0.74 basal segment length of antennular peduncle or to end of segment. Scaphocerite (Fig. 5B) 3 times as long as wide, outer margin slightly concave.  
Mouthparts as figured. Mandible (Fig. 4C) with blunt teeth at extremity of incisor process. Maxillula (Fig. 4D) with simple palp, lower lacinia broadly rounded, upper lacinia broadly elongated, inner edge straight, with dense setae and teeth. Maxilla (Fig. 4E) with slender palp, upper endite subdivided, scaphognathite tapering with numerous long hooked setae posteriorly. Palp of first maxilliped stout (Fig. 4F), terminating in projection. Endopod of second maxilliped (Fig. 5C) with fused dactylus and propodal segments. Third maxilliped (Fig. 5D) reaching to distal end of antennular peduncle, ending in single terminal claw; exopod reaching posterior 0.25 penultimate segment length, ultimate segment shorter than penultimate segment. Epipods on first 4 pereiopods.  
First pereiopod (Fig. 5E) short, stout, reaching slightly beyond end of basal segment of antennular peduncle, merus 2.5 times as long as broad; carpus strong concave anteriorly, 1.3 times as long as high, chela 1.7 times as long as broad, fingers slightly longer than palm. Second pereiopod (Fig. 5F) reaching to end of antennular peduncle, carpus 2.6 times as long as high, chela slightly shorter than carpus, 2.6 times as long as broad, fingers 1.5 times as long as palm. Third pereiopod (Fig. 6A, B) long, reaching slightly beyond distal end of scaphocerite, propodus 10 times as long as broad, 4.3 times as long as dactylus (claw included); dactylus ending in 2 claws, with 2-4 accessory spines on flexor margin. Fifth pereiopod (Fig. 6C, D) reaching distal end of scaphocerite, propodus 13 times as long as wide, 4.9 times as long as dactylus; dactylus with 25 spinules on flexor margin.  
© 2018 Academia Sinica, Taiwan  
© 2018 Academia Sinica, Taiwan  
© 2018 Academia Sinica, Taiwan  
© 2018 Academia Sinica, Taiwan  
Endopod of male first pleopod (Fig. 6E, G) short, reaching to 0.67 endopod length, subrectangular, 3.3 times as long as wide, appendix interna situated at posterior 0.25 endopod length, extending to end of endopod. Appendix masculina of male second pleopod (Fig. 6F, H) slightly curved outwards, reaching 0.75 endopod length; appendix interna of male second pleopod elongated, reaching to middle of appendix masculina.  
Uropodal diaeresis (Fig. 6H) with 9-11 spinules.  
 Habitat: Subterranean river in a karst cave.   
 Etymology: The species is named after the type locality, Alu Cave. The name is used as a noun in apposition.   
 Remarks: Caridina alu sp. nov. resembles Caridina sphyropoda Liang and Zhou, 1993, from Guangxi Province in the form of its rostrum, but can be differentiated by the arrangement of its teeth: in C. alu, the postorbital teeth are widely placed, occupying half the length of the carapace (Fig. 4A, B) (vs. postorbital teeth are closely placed, occupying only a third of the carapace length; cf. Liang and Zhou, 1993: fig. 4(1)); the eyes are degenerated (Fig. 4A, B) (vs. developed; cf. Liang and Zhou, 1993: fig. 4(1)); the endopod is rectangular (Fig. 6G) (vs. sigmoid; cf. Liang and Zhou, 1993: fig. 4(8)), and the telson does not possess a posteromedian projection (Fig. 5G) (vs. projection distinctly present; cf. Liang and Zhou, 1993: fig. 4(2)).   
 Distribution: Yunnan Province (Alu 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 5-9, DOI: 10.6620/ZS.2018.57-27, http://zenodo.org/record/13314991