Monday, June 8, 2020

[Crustacea • 2020] Caridina tricincta & C. pacbo • Two New Freshwater Shrimps of the Genus Caridina H. Milne Edwards, 1837 (Decapoda: Atyidae) from northern Vietnam


Caridina tricincta
 Do, Rintelen & Dang, 2020

RAFFLES BULLETIN OF ZOOLOGY. 68

 Abstract
Two new species of freshwater shrimp in the family Atyidae, Caridina tricincta and C. pacbo, are described from the provinces of Tuyen Quang and Ha Giang, and from the province of Cao Bang, respectively, all in northern Vietnam. The new species can be distinguished from congeners by distinct characteristics of the rostrum, first and second pereopods, and male first and second pleopods. Molecular phylogenetic analysis of the mitochondrial cytochrome oxidase subunit I (COI) and 16S ribosomal RNA (16S) genes also support the distinctiveness of the new species from all other examined species.

Key words: Caridea, Caridina tricincta, Caridina pacbo, taxonomy, Tuyen Quang, Ha Giang, Cao Bang

TAXONOMY
 Family Atyidae De Haan, 1849 

Caridina H. Milne Edwards, 1837

Fig. 4. Caridina tricincta, new species. A, in situ photograph (by Nguyen Anh Tuan) at a stream of Khau Tinh Commune, Na Hang District, Tuyen Quang Province;
B, live individuals collected in Lac Nong Commune, Bac Me District, Ha Giang Province.

Caridina tricincta, new species

Habitat. This species was found in a stream with mixed sand, gravel, and rock substratum, and clear flowing water from the forest (Fig. 4A). 

 Etymology. The name ‘tricincta’ (L. tri – three; cinctus – belt or girdle) refers to the three characteristic transverse stripes on the body of live specimens of this species. Used as an adjective.



Caridina pacbo, new species 

Habitat. This new species was found in a streamlet with mixed sand, gravel, and bedrock substratum, and clear flowing water from the forest (Fig. 7).

Etymology. The new species is named ‘pacbo’ after the type locality name: Pac Bo, Ha Quang, Cao Bang Province, northeast Vietnam. The name is used as a noun in apposition.

Fig. 8. Live colouration of Caridina pacbo, new species.
Fig. 7. Habitat of Caridina pacbo, new species, in Pac Bo village, Truong Ha Commune, Ha Quang District, Cao Bang Province. 


Van Tu Do, Thomas von Rintelen and Van Dong Dang. 2020. Descriptions of Two New Freshwater Shrimps of the Genus Caridina H. Milne Edwards, 1837 (Crustacea: Decapoda: Atyidae) from northern Vietnam. RAFFLES BULLETIN OF ZOOLOGY. 68; 404–420.