Comprehensive DescriptionRead full entry
Rana amamiensis has a moderately slender body and a triangular head which is longer than wide. Its snout is dorsally pointed and projects beyond the lower jaw, with the nostril nearer to the tip of the snout than to the eye. Forelimbs are stout and the fingers are unwebbed, with the tips dilated into small discs with circummarginal grooves. Hindlimbs are rather long, about 2.9 times the length of a forelimb. The heels overlap when the limbs are held at right angles to the body. The tibiotarsal articulation of an adpressed limb reaches far beyond the tip of the snout. Toes are well webbed with thick, not crenulate, webs. The discs on the toes are as wide as those of the two outer fingers. SVL is 57-69 mm in males and 76-101 mm in females.
R. amamiensis frogs have a dorsal color ranging from light brown to greenish, with some individuals lacking dark dorsal markings. The dorsum has tubercles on the sacrum, while the side of the trunk is coarsely granular, and the chest and abdomen are smooth. There is a feeble dorsolateral line formed by short ridges. The supratympanic folds are weak.
R. amamiensis is similar to R. narina in that the inner side of the dorsolateral fold is usually lighter than the ground color. (This condition is never seen in the remaining species of the Rana narina group.) However, R. amamiensis is much larger than R. narina. There is no other large frog within its range that has such a long snout with nostrils at the tip.