Corroboree frog

Pseudophryne corroboree
J. A. Moore 1953
Pseudophryne pengilleyi
Wells and Wellington 1985

There are two species of Corroboree frog, the Southern (P. corroboree) and the Northern (P. pengilleyi). Both are classified as critically endangered on the IUCN Red List, but the former is more at risk due to its extremely restricted range.

'Corroboree' is an aboriginal word for a gathering or meeting, traditionally the attendees paint themeselves with yellow markings similar to those of this frog.

Contents

1 Physical description 2 Range and habitat 3 Biology 4 References 5 External links

Physical description

The corroboree frog has a highly distinctive yellow and black striped skin. Stripes run longitudinally along the back and onto the limbs. The dorsal surface is somewhat granular and lumpy, whilst the belly is smooth and either black and yellow or black and white. Males may reach 28 mm and females 30 mm in length. Toes are not webbed. Calls are like a grating, upward inflected 'ark', similar to P. bibroni and P. dendyi.

This northern form deviates slightly in having narrower yellow to greenish stripes.

Range and habitat

P. corroboree is found only within a fragmented region of less than 10 km² within Mount Kosciuszko National Park in the Snowy Mountains in New South Wales. It is only found at more than 1240 m above sea level (Osborne 1989).

P. pengilleyi ranges across about 550 km² in Namadgi National Park, Australian Capital Territory, and Kosciuszko National Park and Buccleuch State Forest in New South Wales. It is found above about 1000 m.

Both species are restricted to mountain and supalpine woodlands, heathlands and grasslands.

Biology

Sexual maturity of P. corroboree is reached at three years of age, with one year as an embryo/tadpole and two years as a juvenile/subadult. Adults primarily have only one breeding season. Breeding occurs around January-February terrestrially near shallow pools, fens, seepages, wet grassland or wet heaths, where the males build chamber nests within the grasses and moss. Males compete for females via song. The female lays 16-40 eggs and the male grasps her and deposits sperm directly onto the eggs. Tadpoles develop but remain within the protective egg coat until hatching occurs when high ground-water levels after rain cause the nest to become flooded at 4 to 6 months. Tadpole development takes six to eight months. Metamorphsis occurs between December and February (Osborne and Norman 1991).

P. pengilleyi prefers to breed in sphagnum bogs and wet heath in subalpine areas and dense patches of herbs in openings or seepages amongst fallen tussocks at lower elevation (bog pools at high altitudes above 1400 m and in shallow seepage pools in gullies at lower altitudes of 1000-1400 m). Other reproductive details are as for P. corroboree.

Non-breeding habitat for both species occurs in forest, woodland and heath adjacent to breeding sites.

These frogs feed mainly on small invertebrates such as ants.

Corroboree frogs are the first frog discovered that are able to produce their own poisonous alkaloids, as opposed to obtaining it via diet as many other frogs do. The alkaloid is secreted from the skin as a defence against predation, and potentially against skin infections by microbes. The unique alkaloid produced has been named pseudophrynamine (Daly et al 2002).

References

Daly, J. W., H. M. Garraffo, L. K. Pannell and T. F. Spande. 1990. Alkaloids from Australian frogs (Myobatrachidae): Pseudophrynamines and pumiliotoxins. Journal of Natural Products 53(2): 401-421.

Moore, J. A. 1953. A new species of Pseudophryne from Victoria. Proceedings of the Linnean Society of New South Wales 78(3-4): 179-180.

Osborne, W. S. 1989. Distribution, relative abundance and conservation status of Corroboree Frogs, Pseudophryne corroboree (Anura: Myobatrachidae). Australian Wildlife Research 16:537-547.

Osborne, W. S. and J. A. Norman. 1991. Conservation Genetics of Corroboree Frogs Pseudophryne corroboree Moore (Anura: Myobatrachidae): population subdivision and genetic divergence. Australian Journal of Zoology 39:285-297.

External links

• Tidbinbilla Nature Reserve information page, including a photo of a Corroboree frog