occupies the southern arid regions of Australia.
The water-holding frog prefers to live in grasslands, temporary swamps, claypans, and billibongs. Their distribution is limited to southern Australia (S. Australian Frogcensus 1999).
- Terrestrial Biomes
- savanna or grassland
- Aquatic Biomes
- rivers and streams
The water-holding frog is characterized by a broad, flat head, completely webbed toes, and a stout body which is usually dull gray to dark brown or green. They also have small eyes that are placed somewhat laterally and forward-directed, enhancing vision downward and binocular perspective (Cogger and Zweifel 1998). The water-holding frog can also be characterized by its distinct call of a long drawn out "mawww, mawww". The male frogs range in size from 42-64mm, where the females range from 50-72mm (S. Australian Frogcensus 1999).
- Development - Life Cycle
The water-holding frog only emerges from deep underground after it rains to breed. It lays large amounts of spawn in still water after floods. Some eggs may be attached to vegetation, or spread in a thin film on the surface, thus ensuring adequate oxygen in warm waters suffering from oxygen depletion (Cogger and Zweifel 1998). Tadpoles of the water-holding frog can reach a maximum length of 60mm (S. Australian Frogcensus 1999).
- Key Reproductive Features
- gonochoric/gonochoristic/dioecious (sexes separate)
has the ability to undergo an amazing process called aestivation. During hot, dry conditions, the water-holding frog buries itself in the sandy ground and becomes inactive, maintaining a reduced metabolic rate. During aestivation, the water-holding frog secretes mucous from the skin, which lines the chamber and hardens around the frog's body, allowing the frog to hold large amounts of water. This impervious outer skin "cocoon" also prevents desiccation and is torn open by the frog when it emerges from deep underground after it rains (Cogger and Zweifel 1998). Aestivation in many aspects is similar to hibernation, differing only in that hibernation is a response to cold conditions (Withers 1993).
- Key Behaviors
prefers to eat a diet consisting mainly of insects and small fish. The water-holding frog has the rare ability to catch their prey underwater. They do this by using their strong, muscular attributes and lunging at their prey, stuffing it in their mouths.
Economic Importance for Humans: Positive
Because of their unique and unusual ability to retain large amounts of water, the water-holding frog has become the best example of a burrowing frog traditionally used by the Aboriginies. As the water is stored in the bladder or in the pockets of skin, a slight pressure applied by hand causes the frog to release water. The Aboriginal people dig upand enjoy the resource this frog has to offer. This water is very fresh and after the Aboriginies drink, the frog is released unharmed (S. Australian Frogcensus 1999).
Megan Kierzek (author), Michigan State University, James Harding (editor), Michigan State University.
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
- bilateral symmetry
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
having the capacity to move from one place to another.
- native range
the area in which the animal is naturally found, the region in which it is endemic.
- tropical savanna and grassland
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
Cogger, H., R. Zweifel. 1998. Encyclopedia of Reptiles and Amphibians: A Comprehensive Illustrated Guide by International Experts. San Diego: Academic Press.
Southern Australian Frogcensus, 1999. "Southern Australian Frogcensus" (On-line). Accessed November 15, 1999 at http://epa.sa.gov.au/frogcensus/platycep.htm..
Withers, P. 1999. "Research Interests. Aestivation" (On-line). Accessed November 15, 1999 at http://general.uwa.edu.au/u/uwgzool/pcwaest.htm.