We surveyed the population status of the Neotropical toad genus Atelopus, and document recent catastrophic declines that are more severe than previously reported for any amphibian genus. Of 113 species that have been described or are candidates for description, data indicate that in 42 species, population sizes have been reduced by at least half and only ten species have stable populations. The status of the remaining taxa is unknown. At least 30 species have been missing from all known localities for at least 8 yr and are feared extinct. Most of these species were last seen between 1984 and 1996. All species restricted to elevations of above 1000 m have declined and 75 percent have disappeared, while 58 percent of lowland species have declined and 38 percent have disappeared. Habitat loss was not related to declines once we controlled for the effects of elevation. In fact, 22 species that occur in protected areas have disappeared. The fungal disease Batrachochytrium dendrobatidis has been documented from nine species that have declined, and may explain declines in higher elevation species that occur in undisturbed habitats. Climate change may also play a role, but other potential factors such as environmental contamination, trade, and introduced species are unlikely to have affected more than a handful of species. Widespread declines and extinctions in Atelopus may reflect population changes in other Neotropical amphibians that are more difficult to survey, and the loss of this trophic group may have cascading effects on other species in tropical ecosystems. RESUMENExaminamos el estado poblacional de las ranas neotropicales del género Atelopus y documentamos disminuciones catastróficas recientes, las más drásticas señaladas para cualquier género de anfibios. De las 113 especies que han sido descritas o son candidatas para ser descritas, los datos poblacionales indican que en 42 especies, las poblaciones han sido reducidas por lo menos a la mitad y solamente diez especies tienen poblaciones estables. El estado de los taxa restantes es desconocido. Por lo menos 30 especies no han sido vistas en al menos ocho años de todas las localidades conocidas, y se teme que se hayan extinguido La mayoría de estas especies desaparecieron entre 1984 y 1996. Todas las especies con SPECIAL SECTION Declines and Extinctions of Atelopus 191rangos altitudinales de 1000 m o superiores han sufrido disminuciones poblacionales, el 75 por ciento de estas ha desaparecido del todo. El 58 por ciento de las especies de bajura han sufrido disminuciones, mientras que el 38 por ciento ha desaparecido del todo. La pérdida de hábitat, no fue relacionada con las disminuciones una vez que se controló el efecto de altura en los análisis. De hecho, unas 22 especies que tienen poblaciones dentro deáreas protegidas han desaparecido. El hongo quítrido Batrachochytrium dendrobatidis estuvo presente en nueve especies que han experimentado disminuciones y puede explicar desapariciones en especies que ocupan hábitats no perturbados a mayores elevac...
We review the systematics of frogs of the Hyloscirtus larinopygion group. A new phylogenetic tree inferred frommitochondrial DNA (partial sequences of 12S rRNA, valine-tRNA, and 16S rRNA genes; ~2.3 kb) of eleven species ofthe H. larinopygion group is provided, based on maximum parsimony, maximum likelihood, and Bayesian analyses. Ourphylogeny confirms the close relationship of members of the H. larinopygion group with Andean relatives of the H.armatus group, which also occurs in the Andes. Hyloscirtus tapichalaca is placed as sister species to the rest of the H.larinopygion group, in which two clades (A+B) are evident. Although ingroup relationships are well supported, themonophyly of the H. larinopygion group and placement of H. tapichalaca require additional testing. Genetic divergencesamong species of the H. larinopygion group are shallow compared to those observed in many other anurans, with geneticdistance among sister species (H. princecharlesi and H. ptychodactylus) as low as 1.31%. However, this pattern isconcordant with radiations in other highland Andean lineages of anurans that show marked morphological or behavioraldifferentiation, but low divergence in mitochondrial markers. Divergence-time analyses (using BEAST) indicate that theHyloscirtus clade is a relatively ancient lineage that appeared in the Eocene, at a minimum age of 51.2 million years ago(MYA), while the H. larinopygion group originated in the Middle-Late Eocene at a minimum age of 40.9 MYA. Ourresults might suggest a rapid radiation of Hyloscirtus starting in the Miocene into the Pliocene, from at least 14.2 MYA tothe most recent divergence between sister taxa at ~2.6 MYA. We also describe two sympatric new species of Hyloscirtusfrom northwestern Ecuador: H. criptico sp. nov. and H. princecharlesi sp. nov. We diagnose them by their phylogeneticposition (they are not sister to each other), genetic divergence, and a unique combination of color patterns, and othermorphological features. Additionally, we describe the suctorial tadpoles and the extreme ontogenic color changes in H.larinopygion, H. lindae, H. pantostictus, H. princecharlesi, H. psarolaimus, and H. tigrinus. Furthermore, we describe theosteology of H. criptico, H. lindae, H. pacha, H. pantostictus, H. princecharlesi, H. psarolaimus, H. ptychodactylus, andH. staufferorum. We describe vocalizations of H. lindae, H. pacha, H. pantostictus, H. pasarolaimus, H. staufferorum, andH. tapichalaca. Hyloscirtus tigrinus is recorded for the first time in Ecuador and its range is extended 62.4 km (airlinedistance), from its southernmost locality record in Departamento de Nariño, Colombia. Most species of the H.larinopygion group are currently severely threatened by extinction, after surviving the catastrophic extinctions in the1980s and 1990s that led to the disappearance of many other sympatric anurans that bred in swiftly flowing water and hadlotic water tadpoles in the Andean highlands. Research and conservation actions are urgently needed for these species. Inorder to better call attention to these conservation issues, we name one of the new species in honor of Prince Charles ofWales, who is contributing significantly to the growth of awareness in the battle against tropical deforestation, climate change, and the catastrophic extinction of rainforest amphibians.
We present a new phylogeny, based on DNA sequences of mitochondrial and nuclear genes, for frogs of the genus Osteocephalus with emphasis in the Osteocephalus buckleyi species complex. Genetic, morphologic, and advertisement call data are combined to define species boundaries and describe new species. The phylogeny shows strong support for: (1) a basal position of Osteocephalus taurinus + Osteocephalus oophagus, (2) a clade containing phytotelmata breeding species, and (3) a clade that corresponds to the Osteocephalus buckleyi species complex. Our results document a large proportion of hidden diversity within a set of populations that were previously treated as a single, widely distributed species, Osteocephalus buckleyi. Individuals assignable to Osteocephalus buckleyi formed a paraphyletic group relative to Osteocephalus verruciger and Osteocephalus cabrerai and contained four species, one of which is Osteocephalus buckleyi sensu stricto and three are new. Two of the new species are shared between Ecuador and Peru (Osteocephalus vilmae sp. n. and Osteocephalus cannatellai sp. n.) and one is distributed in the Amazon region of southern Peru (Osteocephalus germani sp. n.) We discuss the difficulties of using morphological characters to define species boundaries and propose a hypothesis to explain them.
Osteocephalus festae is an Amazonian species recently resurrected from a synonymy with Osteocephalus buckleyi. Because few specimens are known, its morphological variation, diagnostic characters, and distribution are poorly understood. Herein we determine its phylogenetic relationships and provide a complete taxonomic account based on recently collected specimens (adults and larvae) from nine localities in Ecuador and Peru. Osteocephalus festae is most similar to Osteocephalus verruciger from which it differs in having less tuberculate dorsal skin on males, smaller tympanum, and more tooth rows in the oral disk of larvae. A phylogeny based on mitochondrial DNA sequences, genes 12S and ND1, shows that Osteocephalus festae is closely related to Osteocephalus buckleyi, Osteocephalus mutabor and Osteocephalus verruciger. A clade consisting of Osteocephalus festae, Osteocephalus verruciger, and Osteocephalus buckleyi is characterized by stream dwelling tadpoles. Surprisingly, we found paraphyly among Ecuadorian populations of Osteocephalus buckleyi and Osteocephalus verruciger. The causes for paraphyly are unknown but in Osteocephalus buckleyi may result from the existence of cryptic species.
We describe Engystomops puyango sp. nov. from the lowlands of southwestern Ecuador. The new species is closely related to E. pustulatus from which it differs in skin texture, advertisement call, and karyotype features. The new species also differs from E. pustulatus at genes 12S and 16S of mitochondrial DNA (6.5%–6.8% of sequence divergence). A phylogeny based on mtDNA shows that E. sp. nov. is part of a clade of Engystomops distributed below 1300 m in western Ecuador and northwestern Peru. The new species occurs in Evergreen Lower Montane Forest and Foothill Semideciduous Costa Forest. The karyotype of the new species has 2n = 20 chromosomes which represents the first known reduction in chromosome number in Leiuperidae (2n = 22). Its advertisement calls as well as those of E. pustulatus have a facultative component that resembles the chuck in calls of E. pustulosus but that are less discrete and have lower acoustic complexity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.