Hoplobatrachus tigerinus (Daudin, 1802)

Deuti, Kaushik, Ray, Sukumar, Bag, Probhat & Dey, Swapan Kumar, 2017, Amphibians of the Duars area of Northern West Bengal, Records of the Zoological Survey of India 117 (3), pp. 221-241 : 229

9. Hoplobatrachus tigerinus (Daudin, 1802)

1802. Rana tigerina Daudin, Hist. Nat . Rain. Gren. Crap., Quarto, 1: 42.

Common Name: Bull Frog, Indian Bull Frog (English).

Specimens examined: 5 ex: A 11943 from from Rajabhatkhawa, Buxa Tiger Reserve, Alipurduar district , West Bengal (26°36’839”N, 89°31’929”E) collected on

04.vi.2014; A 11946 from Alipurduar, Alipurduar district , West Bengal (26°44’939”N, 89°34’135”E) collected on

05.vi.2014; A 11962 from from Mendabari, Chilapata forest, Jalpaiguri district , West Bengal (26°36’687”N, 89°23’996”E) collected on 10.vi.2014; A 12441 from CC Line Beat, Chilapata forest, Jalpaiguri district , West Bengal (26°36’847”N, 89°21’086”E) collected on 18.viii.2015 and A 12469 from Ramsai, Gorumara National Park, Jalpaiguri district , West Bengal (26°78’403”N, 88°84’692”E) collected on 12.viii.2015. The measurements of the frogs collected are given below in millimeters :

Distinguishing features: Large frogs with smooth skin and longitudinal glandular folds on the back. They are quite bulky with long and muscular limbs. Head is somewhat pointed and projects beyond the mouth. A skin fold runs from behind the eye to the shoulder. Fingers are without webbing, the tips of the fingers and toes are not sharply pointed. Toes are extensively webbed but the webbing does not reach to the tip of the fourth toe. Belly is smooth with no porous warts on the flanks. Vocal sacs in males are external and blue in colour.

Colour: Yellowish or olive-green with darker leopard-like spots and patches. A yellowish median stripe runs from the tip of the snout to the vent. A broad white band runs along the side. The breeding males turn bright lemon yellow.

Habitat: Found among grasses and bushes and inside hollows at the edge of ponds, ditches and canals. Seen frequently on the edges of water bodies during breeding season into which they leap headlong at the least sign of danger.

Remarks: Very common species in the duars area. They are solitary creatures, which aggregate only during the breeding season. In the non-breeding season, they are silent and difficult to locate but with the appearance of the rainy season their highly resonant call can be heard throughout the night. Croaking loudly the males await the arrival of the females. The eggs are laid in ponds and ditches where they float first but sink later. The tadpoles are bottom-feeders. Reported earlier from West Bengal ( Sarkar, Biswas and Ray, 1992) and Deuti (1995).