Adults. Males to 45 mm, females to 38 mm. Back is dark brown or dark grey with irregular dark blotches and is rough with low ridges or bumps. There is a dark butterfly-shaped marking between the eyes. Throat is usually grey or black with white flecks. Belly is smooth and marbled black or grey and white. Tympanum (eardrum) is not visible. Pupil is horizontal and iris is golden brown. Arms and legs are barred in most, groin and backs of lower legs have bright red patches. Fingers and toes are not noticeably webbed and both lack pads. Males are larger than females, with a much broader head, wider than the body. Males also have two tusk-like protrusions on the front of the lower jaw that can only be seen when the mouth is open.

Larvae. Tadpoles can reach up to 35 mm in length. Body is oval-shaped or elliptical and dark brown, almost black, in colour, sometimes with a cream-coloured patch on the snout. Belly is transparent to grey with fine gold flecks. Iris is copper-gold with a thin ring of the same colour around the pupil. Tail is about as tall as the body and arches only slightly, tapering to a narrow tip. Fins are mostly transparent with fine spots and muscle is dark grey to light brown with gold flecks. Tadpoles metamorphose from December-February, around two months after hatching, though they may overwinter in upland streams.^1,6

Eggs. 100-600 unpigmented eggs are laid as a foamy mass in a nest constructed by the male in streams and at the edges of ponds or dams.¹

Habitat. Inhabits relatively still water, such as slow-flowing streams, dams, ponds, ditches, and flooded grasslands in rainforest, wet sclerophyll forest, and woodland.

Natural Pond

Tamborine Mountain, QLD

Diet. Feeds on beetles, flying insects, spiders, snails, isopods, worms, onychophorans, and small vertebrates, including other frogs.^4,5

Predation & Defence. Likely predators include reptiles, birds, and mammals.

Call is a soft, slowly repeated, clucking ‘Tok-uck.’ Males call from a concealed location within or in close proximity to water, often call during day as well as at night. Breeding usually occurs October-December, but may be heard calling September-March.

In addition the the normal advertisement call (as recorded below) males employ a ‘territorial call,’ a series of short trills, to ward off rival males. Males may also use their ‘tusks’ to bite males who intrude into their territory.⁵

Near Threatened (IUCN Red List 2004)

Listed as Near Threatened because this species is probably in significant decline (but probably at a rate of less than 30% over ten years) because of chytridiomycosis, thus making the species close to qualifying for Vulnerable.³

Not Listed nationally (Environment Protection and Biodiversity Conservation Act 1999)

Vulnerable in Queensland (Nature Conservation Act 1992)

1. Anstis, M. (2017). Tadpoles and Frogs of Australia. Second Edition. New Holland Publishers, Sydney.
2. Cogger, H.G. (2018). Reptiles and Amphibians of Australia. Updated 7th Edition. CSIRO Publishing, Melbourne.
3. Hines, H., Meyer, E., Hero, J.-M., Newell, D. & Clarke, J. (2004). Adelotus brevis. The IUCN Red List of Threatened Species 2004: e.T520A13058936. https://dx.doi.org/10.2305/IUCN.UK.2004.RLTS.T520A13058936.en. Downloaded on 25 April 2020.
4. Hines, H.B. (2012). Tusked Frog (Adelotus brevis). In Queensland’s Threatened Animals, eds. L.K. Curtis, A.J. Dennis, K.R. McDonald, P.M. Kyne, & S. J.S. Debus. CSIRO Publishing, Melbourne.
5. Katsikaros, K. & Shine, R. (1997). Sexual dimorphism in the tusked frog, Adelotus brevis (Anura: Myobatrachidae): the roles of natural and sexual selection. Biological Journal of the Linnean Society 60: 39-51.
6. Meyer, E., Hines, H.B. & Hero, J.-M. (2001). Wet Forest Frogs of South-east Queensland. Griffith University, Brisbane.
7. Atlas of Living Australia occurrence download at https://doi.org/10.26197/5e9a2fc401f43 accessed on Sat Apr 18 08:37:47 AEST 2020.