Pseudophryne covacevichae |
When most people think of poisonous frogs, images of brightly coloured frogs of the South American jungles spring to mind. Whilst these attractive frogs do take all the fame, Australia's Pseudophryne genus despite being less toxic, does contain equally charming and brightly coloured poisonous frogs.
Like the dart frogs of South America the many species in the Pseudophryne genus exhibit bright warning colours as a predator deterrent, a trait know as aposematism. In the case of these Toadlets (Pseudophryne genus) these colours alert the prey to the poisons excreted on the skin (Santos et al. 2003).
Two main toxins have been found on the skin of Pseudophyrne frogs. Pseudophrynamines (PSs) and Pumiliotoxins (PTX) (Smith et al. 2002). Pumiliotoxins are found on the skin of many frog around the world most notably the Phyllobates (South American Poison Dart Frogs) and the Mantilla genus of Madagascar (Santos et al. 2003). The toxin is obtained by the frogs by consuming specific invertebrates in particular beetles. Other animals including some birds have been known to also acquire this toxin from beetles (Daly et al. 2002).
Pseudophryne corroboree |
Refernces
Daly, J.W., Kaneko, T., Wilham, J., Garraffo, H.M., Spande, T.F., Espinosa, A. and Donnelly, M.A. (2002). “Bioactive alkaloids of frog skin: combinatorial bioprospecting reveals that pumiliotoxins have an arthropod source.”, Proceedings of the National Academy of Sciences, Vol: 99, No: 22, pp: 13996-14001.
Santos, J. C., Coloma, L. A., & Cannatella, D. C. (2003). Multiple, recurring origins of aposematism and diet specialization in poison frogs. Proceedings of the National Academy of Sciences of the United States of America, Vol: 100, No: 22, pp: 12792–12797.
Smith, B.P., Tyler, M.J., Kaneko, T., Garraffo, H.M., Spande, T.F. and Daly, J.W.(2002). Evidence for biosynthesis of pseudophrynamine alkaloids by an Australian myobatrachid frog (Pseudophryne) and for sequestration of dietary pumiliotoxins.”, Journal of natural products, Vol: 65, No: 4, pp: 439-447.
Images
P.covacevichae by Nick Weigner
P.corroboree http://www.australiangeographic.com.au/blogs/australian-endangered-species/2014/05/endangered-southern-corroboree-frog ,22/3/16.
That’s pretty cool! I was curious as to how toxic these frogs are? Are they as lethal as their South American counterparts? Can the toxin enter one’s body just by physically touching the skin?
ReplyDeleteThere are no documented cases of any intoxication caused by the frogs, and are safely handled (though doing so is illegal without permits and can put the frog at great risk of stress or infection).
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