The head is broad with a pointed snout. The skin is either smooth or covered with very small tubercles on the back and larger ones on the sides above the arms. The dorsal surface is olive-brown or purplish-brown, featuring a darker, light-edged, hourglass-shaped mark on the head and the anterior part of the back. The breast and belly are spotless and yellowish, while the throat is grey. The toes are fully webbed with swollen tips.