Bioacoustics of Hoplobatrachus tigerinus

( Fig 4I ) Specimens examined: one adult male (WIIAD 228). Morphological features: An adult male, SVL 153.9 mm ; body large and stout; head marginally longer than wide; snout obtusely pointed in dorsal view and projecting beyond mouth; tympanum distinct, nearly equal to the diameter of eye, prominent supratympanic fold; arms short and strong; dorsal skin glandular with broken longitudinal ridges; finger tips without discs, relative length of fingers II <IV <I <III; toes nearly full webbed, webbing formula I0–0II0–½ III½–½ IV ½–½V), relative toes length 1<2<3<5<4, inner metatarsal tubercle present. Coloration in life : Adult male pale brown or greyish (lemon yellowish during breeding season) with dark plump spots on dorsum; prominent greenish or pale yellowish stripe from behind the eye to the groin; a white streak on upper jaw; hind limbs cross-barred with four prominent bands; ventral sides pale white. Males had distinct blue paired subgular vocal sac which is likely to be an optical cue for attraction of females ( Gomez et al . 2009 ; Fig 4I ). Bioacoustics: We analysed 50 advertisement calls from five males of H. tigerinus . The males were recorded calling between 23:30–03:00 hours in July and site air temperature was between 26°C–28.5°C. The mean call duration of analysed calls was 235.30 ± 48.65 ms (181–430 ms). Recorded mean pulse rate was 76.92 ± 5.32 pulses/s (61.82–87.18 pulses/s) with 17.36 ± 2.88 pulses (13–29 pulses) delivered per call. The mean dominant frequency was 1819.14 ± 388.87 Hz (1205.90–2239.50 Hz).