Macrobrachium irwini sp. nov., a new species of freshwater shrimp from Western Ghats, India (Caridea: Palaemonidae)

A new species of the freshwater shrimp of the genus Macrobrachium irwini sp. nov., is described from the Nandhini River near Kateel, Karnataka region of Western Ghats, India. 11 specimens of Macrobrachium irwini sp. nov. were collected from Nandhini river running through a secondary forest with heavily vegetated banks. The morphological analyses revealed that the new species can be clearly distinguished from the closely related species, M. snpurii and M. scabriculum based on the shape and dentition on rostrum, antennular peduncle, segmental ratios of first pereiopod, tubercles along the cutting edges of immovable and movable fingers of second major pereiopod and telson. Additionally, we provided the striking colour patterns on the new species which could be distinguish this species from congeneric species.