Caridina disjuncta Cai and Liang, 1999

Ng, Y. Cai and P. K. L. & Ng, Cai P. K. L., 2010, revision of Caridina yunnanensis and its allied species (Crustacea: Decapoda: Caridea: Atyidae) from Yunnan, southern China, with description of one new species, Journal of Natural History 35, pp. 213-227 : 222-223

Caridina disjuncta Cai and Liang, 1999

(®gure 7) Caridina disjuncta Cai and Liang, 1999: 73 , ®gures 1±4 (type locality: Shilin village , Lunan County, central Yunnan) .

Material examined

HOLOTYPE:, l cl. 48 mm ( SFU 83-72 - 01 ), Shilin (Stone Forest) village , Lunan County, central Yunnan, 8 May 1983.

PARATYPES: Three ll, cl. 5.0 mm, ®ve mm, cl. 5.0± 6.4 mm, two mm (ovigerous), cl. 6.0 mm ( SFU), data same as holotype .

Diagnosis

Rostrum straight, reaching to middle of second segment of antennular peduncle or end of this segment, rostral formula 5±6 (mode 6)1 5±9/0±2 (mode 0). Teeth on dorsal margin arranged in two groups, separated by distinct gap. First pereiopod short with carpus 1.6±1.9 times as long as high; chela 2.0±2.3 times as long as broad, ®ngers 1.5±1.6 times as long as palm. Second pereiopod with carpus 4.2±4.8 times as long as high; chela slightly shorter than carpus, 2.7±2.9 times as long as broad; ®ngers 1.5±1.6 times as long as palm. Third pereiopod with propodus 3.2±3.8 times as long as dactylus. Fifth pereiopod with propodus 3.6±4.3 times as long as dactylus, with 40±45 spinules on ¯exor margin. Endopod of male ®rst pleopod sub-triangular, 3.2 times as long as wide at base, appendix interna slender, reaching to distal margin of endopod. Appendix masculina of male second pleopod slender, armed on inner margin with two rows of strong spines. Appendix interna short, ca 0.25 times as long as appendix masculina. Uropodal diaeresis with 15±16 spinules.

Remarks

Caridina disjuncta can readily be separated from other members of the species group by the unusual form of the rostrum, in which the dorsal rostral teeth are separated in two groups, and ventral teeth are very scarce. Caridina disjuncta can be distinguished from C. yunnanensi s by the fewer number of ventral rostral teeth (zero to two (mode 0) vs ®ve to ten in C. yunnanensi s), and the stouter carpus of the ®rst pereiopod which is 1.6±1.9 times as long as high (vs 2.0±2.1 times). It can be distinguished from C. disparidentata by its smaller egg size (1.15± 1.25 Ö 0.78±0.84 mm vs 1.31± 1.40 Ö 0.81±0.98 mm), and the stouter carpus of the ®rst pereiopod (1.6 ±1.9 times as long as high vs 1.9±2.2 times). Caridina disjuncta is separated from C. mongziensis by its smaller egg size (1.15± 1.25 Ö 0.78±0.84 mm vs 1.35± 1.59 Ö 0.93±1.07 mm), and the longer ®ngers of the ®rst pereiopod (1.5±1.6 times vs 1.1±1.2 times).