Cosmocerca bengalensis sp. nov. (Nematoda: Cosmocercidae) in Hoplobatrachus tigerinus (Daudin, 1803) (Amphibia, Anura, Dicroglossidae) from West Bengal, India.

Cosmocerca bengalensis sp. nov. (Ascaridida, Cosmocercidae) recovered from the rectum of an Indian bullfrog, Hoplobatrachus tigerinus (Daudin, 1803), collected from Hetampur town in Birbhum district of West Bengal, India, is described and illustrated. This species is similar to C. acanthurum, C. banyulensis, C. cruzi, C. japonica, C. kalesari, C. microhylae, C. novaeguineae, C. ornata, C. paraguayensis, C. parva, C. podicipinus and C. travassosi in having 5 pairs of plectanes supporting preanal papillae but differs from these species by general morphometry, absence of somatic papillae in females, absence of gubernaculum and having only one pair of adanal papillae in males and one pair postanal papillae in females except C. microhylae. Present parasites differ from C. microhylae by absence of gubernaculum and general morphometry. Cosmocerca bengalensis sp. nov. represents the thirtheith species assigned to the genus, seventh from Oriental region and fifth species from India.