The genus Protosticta Selys, 1885 has 10 species reported from the Indian region, of which seven are known from the Western Ghats. Here we report a new species, Protosticta ponmudiensis from the Ponmudi Hills, Thiruvananthapuram District, Kerala, in the Agasthyamalai region of the southern Western Ghats. The species is distinguished from other Protosticta based on its large size, bright green eyes, the broad dorsal stripe on the base of segment 7, and very distinct anal appendages.