Que no está extinta. Simplemente que existían dos especies, donde las mayores diferencias estaban en la presencia de cola en las crías tras el cuidado parental del macho a éstas, la morfología de la nariz y de las patas.
Esta especie del norte habitaba lo que es la cordillera de la costa del Maule fundamentalmente, la cual fue violada a partir de los '70 y donde su habitat desapareció sencillamente en favor de las plantaciones de pino y eucalipto a escala masiva.
Pero la otra especie, la más emblemática y que Darwin conoció de hecho en pleno Vadivia (en el "Origen de las Especies" hay un pasaje donde habla de la abundancia de ésta en esa ciudad), a pesar de estar en peligro de exintción no ha desaparecido. Simplemente que está por esa senda al presentar poblaciones áltamente fragmentadas y ahora algunas con el caso de este infame hongo que está diseminando a nivel Mundial desde mediados de los '80 a todos los anfibios del Mundo. Si no preguntadles a las personas de Costa Rica o Panamá, donde el brote comenzó y han sido las zonas más afectadas.
Os dejo los dos estudios de PLOS (son gratuitos) que se han publicado este año sobre las
Rhinoderma :
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0066957
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0079862
Soto-Azat C, Valenzuela-Sánchez A, Collen B, Rowcliffe JM, Veloso A, et al. (2013) The Population Decline and Extinction of Darwin’s Frogs. PLoS ONE 8(6): e66957.
Darwin’s frogs (Rhinoderma darwinii and R. rufum) are two species of mouth-brooding frogs from Chile and Argentina. Here, we present evidence on the extent of declines, current distribution and conservation status of Rhinoderma spp.; including information on abundance, habitat and threats to extant Darwin’s frog populations. All known archived Rhinoderma specimens were examined in museums in North America, Europe and South America. Extensive surveys were carried out throughout the historical ranges of R. rufum and R. darwinii from 2008 to 2012. Literature review and location data of 2,244 archived specimens were used to develop historical distribution maps for Rhinoderma spp. Based on records of sightings, optimal linear estimation was used to estimate whether R. rufum can be considered extinct. No extant R. rufum was found and our modelling inferred that this species became extinct in 1982 (95% CI, 1980–2000). Rhinoderma darwinii was found in 36 sites. All populations were within native forest and abundance was highest in Chiloé Island, when compared with Coast, Andes and South populations. Estimated population size and density (five populations) averaged 33.2 frogs/population (range, 10.2–56.3) and 14.9 frogs/100 m2 (range, 5.3–74.1), respectively. Our results provide further evidence that R. rufum is extinct and indicate that R. darwinii has declined to a much greater degree than previously recognised. Although this species can still be found across a large part of its historical range, remaining populations are small and severely fragmented. Conservation efforts for R. darwinii should be stepped up and the species re-classified as Endangered.
Soto-Azat C, Valenzuela-Sánchez A, Clarke BT, Busse K, Ortiz JC, et al. (2013) Is Chytridiomycosis Driving Darwin’s Frogs to Extinction? PLoS ONE 8(11): e79862.
Darwin’s frogs (Rhinoderma darwinii and R. rufum) are two species of mouth brooding frogs from Chile and Argentina that have experienced marked population declines. Rhinoderma rufum has not been found in the wild since 1980. We investigated historical and current evidence of Batrachochytrium dendrobatidis (Bd) infection in Rhinoderma spp. to determine whether chytridiomycosis is implicated in the population declines of these species. Archived and live specimens of Rhinoderma spp., sympatric amphibians and amphibians at sites where Rhinoderma sp. had recently gone extinct were examined for Bd infection using quantitative real-time PCR. Six (0.9%) of 662 archived anurans tested positive for Bd (4/289 R. darwinii; 1/266 R. rufum and 1/107 other anurans), all of which had been collected between 1970 and 1978. An overall Bd-infection prevalence of 12.5% was obtained from 797 swabs taken from 369 extant individuals of R. darwinii and 428 individuals representing 18 other species of anurans found at sites with current and recent presence of the two Rhinoderma species. In extant R. darwinii, Bd-infection prevalence (1.9%) was significantly lower than that found in other anurans (7.3%). The prevalence of infection (30%) in other amphibian species was significantly higher in sites where either Rhinoderma spp. had become extinct or was experiencing severe population declines than in sites where there had been no apparent decline (3.0%; x2 = 106.407, P<0.001). This is the first report of widespread Bd presence in Chile and our results are consistent with Rhinoderma spp. declines being due to Bd infection, although additional field and laboratory investigations are required to investigate this further.
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Chile
