Snout to vent length: 2.2-5.1 cm (females larger). Adult and juveniles are variable in colour, ranging from light brown, tan, grey-green to charcoal. Lighter coloured individuals may have irregular dark spots on back. The skin is covered with minute bumps giving the frog a ‘pebbly’ appearance. A light-coloured bar or triangle between the eyes and snout is common, a dark broken line extends from the tip of the snout along the eye to the end of the head. Unlike other frogs the head does not exhibit a tympanum (ear) and the pupil is vertical. Outermost toes on the hind feet are flattened and wide. This species does not have an ability to vocalize like other frog species. Tadpoles range from brownish-grey to reddish-brown or black and are up to 3 cm long prior to metamorphosis. In some populations (e.g. US), the tail has a white tip. The head is relatively flat and the tail is laterally compressed to provide streamlining in fast flows. Tailed Frog tadpoles have suction like mouth parts with rows of teeth on the top and bottom, allowing them to anchor to rocks (and other surfaces) in fast flowing water.