Nyctibatrachus

Radhakrishnan, C., Dinesh, K. P. & Ravichandran, M. S., 2007, A new species of Nyctibatrachus Boulenger (Amphibia: Anura: Nyctibatrachidae) from the Eravikulam National Park, Kerala, India, Zootaxa 1595 (1595), pp. 31-41 : 39

Key to the species of Nyctibatrachus

The following key is based on readily observable morphological characters of the sexually mature adults. The sexually mature adults of the two species should also be distinguished by the presence of either of femoral glands or vocal sacs or some times both in males and only mature ova in the females except for N. sylvaticus where no data is available for sexual dimorphism.

1 Skin of dorsum smooth................................................................................................................................ 2

- Skin of dorsum with closely set folds.......................................................................................................... 5

2 Webbing on the toes is less than 1/4 th or rudimentary ................................................................................ 3

- Toes half or more than half webbed............................................................................................................. 4

3 Tibiotarsal articulation reaches the tip of the snout; limbs cross barred ......................................... beddomei

- Tibiotarsal articulation not reaching the eye; limbs without cross bars ................................ kempholeyensis

4 Toes ½ webbed, dorsum smooth with few glandular folds, tips of finger and toes without discs ............... .................................................................................................................................................... deccanensis

- Toes fully webbed, web reaching posterior border of all the discs ................................................... vasanthi

5 Toes free; a dorsolateral glandular fold and a series of short glandular lines on the dorsum; X markings on the anterior body present ..................................................................................................................... minor

- Toes webbed ................................................................................................................................................ 6

6 Toes less than half webbed or half webbed ................................................................................................. 7

- Toes more than half webbed ........................................................................................................................ 9

7 Toes 1/4 th webbed, heels touching when limbs are folded right angles to body .................................. sholai

- Toes half webbed ......................................................................................................................................... 8

8 Canthus rostralis present ................................................................................................................. sylvaticus

- Canthus rostralis absent .......................................................................................................... sanctipalustris

9 Size comparatively small, toes 3/4 th webbed; dorsum dark brown with light cream blotches; irregular, scattered ridges on dorsum ................................................................................................................. aliciae

- Size medium to large ................................................................................................................................. 10

10 Toes more than half webbed; hands and foot with discs; circum marginal grooves absent on fingers ......... .............................................................................................................................................................. major

- Toes fully webbed...................................................................................................................................... 11

11 Subarticular tubercles feebly prominent, one or two tubercles on the hand ................................... humayuni

- Subarticular tubercles prominent numbering one on first and second fingers, and two on third and fourth fingers, with prominent palmar tubercles .................................................................................................. 12

12 Size large (SVL 27.5 to 43.2 mm), narrow waist, supra tympanic fold weak, subarticular tubercles round .......................................................................................................................................................... petraeus

- Size very large (SVL 52 to 84 mm), diameter behind shoulder and at waist sub equal, distinct supra tympanic fold with another fold from posterior corner of eye to angle of jaw, subarticular tubercles distinct and oval .................................................................................................................................. karnatakaensis