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2.
Nature ; 622(7982): 308-314, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37794184

RESUMEN

Systematic assessments of species extinction risk at regular intervals are necessary for informing conservation action1,2. Ongoing developments in taxonomy, threatening processes and research further underscore the need for reassessment3,4. Here we report the findings of the second Global Amphibian Assessment, evaluating 8,011 species for the International Union for Conservation of Nature Red List of Threatened Species. We find that amphibians are the most threatened vertebrate class (40.7% of species are globally threatened). The updated Red List Index shows that the status of amphibians is deteriorating globally, particularly for salamanders and in the Neotropics. Disease and habitat loss drove 91% of status deteriorations between 1980 and 2004. Ongoing and projected climate change effects are now of increasing concern, driving 39% of status deteriorations since 2004, followed by habitat loss (37%). Although signs of species recoveries incentivize immediate conservation action, scaled-up investment is urgently needed to reverse the current trends.


Asunto(s)
Anfibios , Cambio Climático , Ecosistema , Especies en Peligro de Extinción , Animales , Anfibios/clasificación , Biodiversidad , Cambio Climático/estadística & datos numéricos , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/tendencias , Especies en Peligro de Extinción/estadística & datos numéricos , Especies en Peligro de Extinción/tendencias , Extinción Biológica , Riesgo , Urodelos/clasificación
4.
Zootaxa ; 4750(1): zootaxa.4750.1.1, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32230050

RESUMEN

Expeditions to unexplored or little explored places are important for discovering new species and also for collecting new samples (including specimens and tissues for DNA sequencing ) that may help resolve a plethora of taxonomic problems. In the 19th century, several naturalists explored a number of localities in Amazonia, describing species for which type material was deposited, mostly, in European museums of natural history. Some of these types were lost or destroyed in World War II and recent expeditions have focused on sampling new material from the type localities. material from Boana cinerascens, which allowed us to infer phylogenetic relationships of the Boana punctata group (i.e., green Boana), based on DNA sequence data, and to revaluate the status of B. cinerascens and its synonyms. We designate, redescribe and illustrate a neotype for B. cinerascens, which was described by Spix in 1824, from the Municipality of Tefé, State of Amazonas, Brazil. We revalidate, redescribe, and illustrate Hyla granosa gracilis Melin, 1941(= Boana gracilis). Corroborating previous studies, the green Boana were not recovered as a monophyletic group. Boana cinerascens is sister of B. gracilis plus a clade containing B. atlantica + B. punctata (both species not recovered as monophyletic).


Asunto(s)
Anuros , Animales , Secuencia de Bases , Filogenia , Análisis de Secuencia de ADN
5.
Zootaxa ; 3693: 387-94, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26185857

RESUMEN

We describe a new species of Microcaecilia from the Guianan region of Brazil, based on a series of eight specimens from the states of Pará and Amazonas. Microcaecilia marvaleewakeae sp. nov. is very similar to M. taylori, but differs from it in having more primary annuli, more secondary grooves, and more secondary grooves that completely encircle the body. The new species also seems to have a relatively shorter and thinner head than M. taylori, but additional specimens of the new species are necessary to check this. A brief discussion of the taxonomy of M. taylori is presented.


Asunto(s)
Anfibios/anatomía & histología , Anfibios/clasificación , Distribución Animal/fisiología , Anfibios/fisiología , Animales , Brasil , Femenino , Especificidad de la Especie
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