A new species of ranid frog of the genus Nyctibatrachus is described from Castle Rock, Karnataka State, Southwest India. The new species is compared with all known congeners and is diagnosed by the following combination of characters: head wider than long; snout projecting beyond mouth; supratympanic fold poorly defined; webbing on toes reaching base of disks except on Toe IV, where it reaches distal subarticular tubercle; tips of digits on fingers and toes flattened to form disks with distinct grooves separating dorsum of disks from venter; and femoral gland present. The largest specimen in the type series has a snout-vent length of 43.2 mm. Nyctibatrachus hussaini Krishnamurthy, Reddy and Gururaja, 2001, is shown to be an invalid nomen, for lack of typification.