A new species of the genus Chauhanellus Bychowsky et Nagibina, 1969 (Monogenea) from the gills of a sea fish Tachysurus dussumieri (Val.) from Andhra Pradesh, India.

Chauhanellus chauhani sp. n., collected from the gills of a sea cat-fish, Tachysurus dussumieri (Valenciennes) from the Bay of Bengal, off the coast of Kakinada, Andhra Pradesh, India is described and illustrated. It differs from the related species of the genus--C. oculatus, C. flexiosus, C. australis, C. nagibinae, and C. pedunculatus--in the shape and articulation of accessory piece with cirrus and in having a crescentic posteromedian process on its dorsal bar. It has five transverse hard structures on the ventral surface of peduncular region, by which it differs from C. oculatus and C. australis the latter have 10-11 and 3 such hard structures, respectively.