There is no exact figure for this. According to the Australian Biological Resources Study (see the related link from the Australian Government website below), there are between 4950 and 6515 described species of amphibians in the world.
The number continues to change as new species of amphibians are being discovered, and others become extinct.
There are nearly 5000 species of frogs.
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There are 17 species of the green tree frog.
In the order, Anura, there are 5,250 species in 33 families.
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A poison dart frog is a rare species of poisonous frog found in Central and South America. Many of these species are threatened due to habitat loss.
there are 12,000 species of fros in rainforests
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There are probably at least 80 species that are endemic (occur only in New Zealand
species
There are many different species of frog in austrailia, and just as many answers to this question. Frog development depends on which kind of frog we are discussing, not on which continent the animal is from.
check out nz threatened species