Between 129 and 221 new species of frogs have been identified in Madagascar, practically doubling the currently known amphibian fauna. The finding suggests that the number of amphibian species in Madagascar, one of the world’s biodiversity hotspots, has been significantly underestimated. According to the researchers, if these results are extrapolated at a global scale, the number of amphibian species worldwide could double.
Their study, conducted with participation of the Spanish Scientific Research Council (CSIC), is published in the journal Proceedings of the National Academy of Science.
As Professor David R. Vieites, CSIC researcher at the Spanish National Natural Sciences Museum in Madrid, states: “the diversity of species in Madagascar is far from being known and there is still a lot of scientific research to be done. Our data suggest that the number of new species of amphibians not only has been underestimated but it is spatially widespread, even in well studied areas. For example, two of the most visited and studied National parks, Ranomafana and MantadÃa/Analamazaotra, harbour 31 and 10 new species respectively.”
Dr. Frank Glaw, curator of herpetology at the Zoologische Staatssammlung from Munich explains: ”During the past 15 years, we discovered and described over 100 new frog species from Madagascar, which led us to believe that our species inventory is almost complete. But as our new surveys show, there are many more species than we suspected.”
The paper suggests that the total biodiversity on the island could be much higher also in other groups, so the actual destruction of natural habitats may be affecting more species than previously thought. This is important for conservation planning, as the rate of destruction of rainforests in Madagascar has been one of the highest in the planet, with more than 80% of the historic surface of rainforest already lost.
“Although a lot of reserves and national parks have been created in Madagascar during the last decade, the actual situation of politic instability is allowing the cut of the forest within national parks, generating a lot of uncertainty about the future of the planned network of protected areas,” explains Vieites. Almost a quarter of the new species discovered have not been found yet in protected areas.
Biodiversity
The study proposes different criteria -- morphological, genetic and bioacoustic -- to assign the candidate species (the ones which have been identified as potential new species but not yet formerly described) to different categories. In Madagascar, the number of candidate species is higher than the number of described species in some genera.
“Using these criteria and the integration of different techniques under the principle of congruence could help to boost the inventory and the process of species description worldwide,” explains Vieites. Dr. Miguel Vences, professor at the Technical University of Braunschweig adds: "People think that we know which plant and animal species live on this planet. But the century of discoveries has only just begun – the majority of life forms on Earth is still awaiting scientific recognition."
Also participating in the study were researchers from the Technical University of Braunschweig, Museo regionale di Scienze Naturali from Torino, and the Hessisches Landesmuseum from Darmstadt.
Madagascar is the fourth largest island in the world and one of the most biodiverse areas globally, with a high degree of endemic species. “To get an idea of its biodiversity, while in the Iberian Peninsula are about 30 species of amphibians and in Germany about 20, in a single locality in Madagascar we can find ca. 100 species of frogs,” explains Vieites.