Morphological and Molecular Taxonomy of Selected Species of the Genus Caridina H. Milne Edwards (Atyidae) from Kerala Water ,India

Abstract- Atyid shrimps are ecologically important components of tropical and subtropical aquatic ecosystem. They are well known to play a vital role in food webs of freshwater ecosystem by clearing the debris and microalgae. Besides they are being preyed upon by fishes; in fact due to their small size, atyid shrimps are commercially cultured to serve as forage organisms for ornamental fishes in aquariums. Some of the caridinian shrimps are beautifully coloured and have wide acceptance as representatives of aquariums.

Family Atyidae consists of 43 genera globally and only one genus Caridina H. Milne Edwards has been the representative from India so far. Globally around 290 species under this genus have been recorded though, 28 of them have been found distributed in India. Out of 28 species reported from India, 18 of them are observed in Kerala waters.

The present study is a reinforced approach of morphological and molecular taxonomy of freshwater shrimps belonging to the genus Caridina H. Milne Edwards 1837. Detailed morphological and molecular taxonomic studies of four species under genus Caridina, namely, Caridina natarajani, Caridina pseudogracilirostris, Caridina gracilipes and Caridina jalihali along with two variants of C. natarajani have been undertaken. The barcode data is generated for Caridina natarajani for the first time. It inferred that this species is 23-27% genetically divergent from the other species under Genus Caridina reported at NCBI site and hence the current study emphasizes that C. natarajani is a valid species.