Archey's frog is New Zealand's smallest, and perhaps most beautiful native frog species. It is distinctive in both its terrestrial lifestyle and its archaic form, belonging to one of the most ancient lineages of amphibians on the planet.
They are perfectly adapted to their forest environments with their dorsal (upper) surfaces matching the surrounding vegetation. Typically they are light to dark brown, green-brown, or green with dark brown or black blotches and occasionally brilliant green mottling. Dorsolateral lumps (glandular ridges) are present on the dorsal and dorsolateral surfaces. Their lateral surfaces (sides) are brown, pinkish, or orange-brown with black blotches, flecks, and sometimes green mottling. Similar markings can be seen on the arms and legs of this species, with the legs often bearing distinct dark or green transverse bands. Occasionally, the lower lateral surfaces and upper limbs bear brilliant orange or even pale blue colouration. Black markings are typically present under the eyes and upper lip. Ventral (lower) surfaces are typically black or dark brown and may be mottled with green, pale blue, or yellow. Eye colour black with a light golden or golden-brown upper portion. Feet are unwebbed with thin toes, due in large part to their terrestrial nature. As with other Leiopelma, Archey's frogs show slight sexual dimorphism, with females being larger than males (van Winkel et al. 2018).
Archey’s frogs are similar in appearance to our other native frog species but can be differentiated by a combination of their smaller size, terrestrial nature, often brilliant colouration, and lack of webbing on the hindlimb. They co-occur with the semi-aquatic Hochstetter's frog (Leiopelma hochstetteri) on the Coromandel Peninsula, and in the King Country, but are much smaller, and lack webbing.
