Centro de Investigación de la Biodiversidad y Cambio Climático
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BIOLOGICAL and ECOLOGICAL ASPECTS of the SPECTACLED BEAR (Tremarctos ornatus, Ursidae) in the ECUADOREAN ANDEAN ZONE and CONSERVATION PERSPECTIVES under the LANDSCAPE SPECIES APPROACH [ASPECTOS BIOLÓGICOS Y ECOLÓGICOS DEL OSO DE ANTEOJOS (Tremarctos ornatus, Ursidae) EN LA ZONA ANDINA DE ECUADOR Y PERSPECTIVAS PARA SU CONSERVACIÓN BAJO EL ENFOQUE DE ESPECIES PAISAJE]

2019 , Guillén P.S. , Moretta P.Y.

The Andean bear (Tremarctos ornatus) has inhabited South America for more than five million years, and he is the only living representative of the short-nosed bears, a group that only lived on the American continent. In Ecuador he is considered an endangered species, mainly because the loss of natural habitats in the Andes, due to the pressure of productive anthropic activities (mainly, livestock and agriculture) and extraction of natural resources. This bear is a mammal that needs large areas to eat and find a mate. The Andean bear is important for cloud forests and paramos due to his efficient role as seed scatter. In this work, the’landscape species’ theoretical approach is applied in order to propose activities to conserve the Andean bear and the places that inhabits. This approach also allows to evaluate in a systematic way the quality of the landscape in terms of biological requirements of the species (here, Tremarctos ornatus) and the landscape human uses; likewise, it also considers the size and limits of the conservation area and its internal variation. © 2019, Universidad Politécnica Salesiana, Ecuador.

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Unlocking the potential of snake venom-based molecules against the malaria, Chagas disease, and leishmaniasis triad

2023 , Almeida J.R., Gomes A. , Mendes B. , Aguiar L. , Ferreira M. , Brioschi M.B.C. , Duarte D. , Nogueira F. , Cortes S. , Salazar Valenzuela, David , Miguel D.C. , Teixeira C. , Gameiro P. , Gomes P.

Malaria, leishmaniasis and Chagas disease are vector-borne protozoal infections with a disproportionately high impact on the most fragile societies in the world, and despite malaria-focused research gained momentum in the past two decades, both trypanosomiases and leishmaniases remain neglected tropical diseases. Affordable effective drugs remain the mainstay of tackling this burden, but toxicicty, inneficiency against later stage disease, and drug resistance issues are serious shortcomings. One strategy to overcome these hurdles is to get new therapeutics or inspiration in nature. Indeed, snake venoms have been recognized as valuable sources of biomacromolecules, like peptides and proteins, with antiprotozoal activity. This review highlights major snake venom components active against at least one of the three aforementioned diseases, which include phospholipases A2, metalloproteases, L-amino acid oxidases, lectins, and oligopeptides. The relevance of this repertoire of biomacromolecules and the bottlenecks in their clinical translation are discussed considering approaches that should increase the success rate in this arduous task. Overall, this review underlines how venom-derived biomacromolecules could lead to pioneering antiprotozoal treatments and how the drug landscape for neglected diseases may be revolutionized by a closer look at venoms. Further investigations on poorly studied venoms is needed and could add new therapeutics to the pipeline. © 2023 The Authors

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Molecular phylogenetics of stream treefrogs of the Hyloscirtus larinopygion group (Anura: Hylidae), and description of two new species from Ecuador

2012 , Coloma L.A. , Carvajal-Endara S. , Dueñas J.F. , Paredes-Recalde A. , Morales-Mite M. , Almeida-Reinoso D. , Tapia E.E. , Hutter C.R. , Toral E. , Guayasamin, Juan M.

We review the systematics of frogs of the Hyloscirtus larinopygion group. A new phylogenetic tree inferred from mitochondrial DNA (partial sequences of 12S rRNA, valine-tRNA, and 16S rRNA genes; ∼2.3 kb) of eleven species of the H. larinopygion group is provided, based on maximum parsimony, maximum likelihood, and Bayesian analyses. Our phylogeny 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, the monophyly of the H. larinopygion group and placement of H. tapichalaca require additional testing. Genetic divergences among species of the H. larinopygion group are shallow compared to those observed in many other anurans, with genetic distance among sister species (H. princecharlesi and H. ptychodactylus) as low as 1.31%. However, this pattern is concordant with radiations in other highland Andean lineages of anurans that show marked morphological or behavioral differentiation, but low divergence in mitochondrial markers. Divergence-time analyses (using BEAST) indicate that the Hyloscirtus 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. Our results might suggest a rapid radiation of Hyloscirtus starting in the Miocene into the Pliocene, from at least 14.2 MYA to the most recent divergence between sister taxa at ∼2.6 MYA. We also describe two sympatric new species of Hyloscirtus from northwestern Ecuador: H. criptico sp. nov. and H. princecharlesi sp. nov. We diagnose them by their phylogenetic position (they are not sister to each other), genetic divergence, and a unique combination of color patterns, and other morphological 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 the osteology of H. criptico, H. lindae, H. pacha, H. pantostictus, H. princecharlesi, H. psarolaimus, H. ptychodactylus, and H. staufferorum. We describe vocalizations of H. lindae, H. pacha, H. pantostictus, H. pasarolaimus, H. staufferorum, and H. tapichalaca. Hyloscirtus tigrinus is recorded for the first time in Ecuador and its range is extended 62.4 km (airline distance), 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 the 1980s and 1990s that led to the disappearance of many other sympatric anurans that bred in swiftly flowing water and had lotic water tadpoles in the Andean highlands. Research and conservation actions are urgently needed for these species. In order to better call attention to these conservation issues, we name one of the new species in honor of Prince Charles of Wa l e s, who is contributing significantly to the growth of awareness in the battle against tropical deforestation, climate change, and the catastrophic extinction of rainforest amphibians. Copyright © 2012 · Magnolia Press.

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Rediscovery of the nearly extinct longnose harlequin frog Atelopus longirostris (Bufonidae) in Junín, Imbabura, Ecuador

2017 , Tapia E.E. , Coloma L.A. , Pazmiño-Otamendi G. , Peñafiel N.

We report the recent finding of four adults of Atelopus longirostris, a Critically Endangered species that was last seen in 1989, when catastrophic Atelopus declines occurred. The rediscovery of A. longirostris took place in a new locality, Junín, 1250–1480 m asl, Provincia Imbabura, Ecuador, on 28–31 March 2016. The four frogs were found in two isolated small patches of native forest in a fragmented area heavily modified for agriculture and livestock; one patch protected by the Junín Community Reserve, and another non-protected private patch near the reserve. We found high prevalence of Batrachochytrium dendrobatidis (Bd) in the amphibian community of Junín, but A. longirostris tested negative. The finding of A. longirostris after 27 years is surprising and fits an apparent pattern of mild conditions that might be promoting either the recovery or persistence in low numbers of some relict amphibian populations. The frogs are the first founders of an ex situ assurance colony in Jambatu Research and Conservation Center. Expansion of the Junín Community Reserve is urgently needed to add the currently non-protected patch of forest, where A. longirostris also occurs. The restoration of the forest in degraded areas between both forest patches and in the related river margins is also necessary. This restoration will grant the connectivity between both isolated metapopulations and the normal movement of individuals to the breeding sites in the Chalguayacu and Junín River basins. The latter should be protected to prevent any kind of water pollution by the opencast copper exploitation of the mining concession Llurimagua, which is underway. Atelopus longirostris belongs to a group of at least 29 species of Ecuadorian Atelopus that are critically endangered, 15 of which remain unsighted for at least one decade, and most of them might be extinct. Further synchronous, multidisciplinary and integrative research is needed, aiming to understand the most aspects of the biology of species of Atelopus to support in situ and ex situ conservation actions. © 2017, © 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

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Harlequin frog rediscoveries provide insights into species persistence in the face of drastic amphibian declines

2022 , Jaynes, K.E. , Páez-Vacas, M.I. , Salazar Valenzuela, David , Guayasamin, J.M. , Terán-Valdez, A. , Siavichay, F.R. , Fitzpatrick, S.W.

Amphibians face global declines, and it remains unclear the extent to which species have responded, and through what mechanisms, to persist in the face of emerging diseases and climate change. In recent years, the rediscovery of species considered possibly extinct has sparked public and scientific attention. These are hopeful cases in an otherwise bleak story. Yet, we know little about the population status of these rediscovered species, or the biology underlying their persistence. Here, we highlight the iconic Harlequin frogs (Bufonidae: Atelopus) as a system that was devastated by declines but now encompasses between 18 and 32 rediscoveries (25–37 % of possible extinctions) in the last two decades. Geographic distributions of rediscoveries closely match regional described species abundance, and rediscoveries are documented at elevations from 100 m to >3500 m, with no significant differences between mean historical and contemporary elevations. We also provide genomic data on six decimated species, with historical sample comparisons for two of the species and find a pattern of decreasing genetic variation the longer a species had been missing. Further, we document marked decrease in heterozygosity in one species, but not the other, indicating potential idiosyncratic consequences of declines. Finally, we discuss research priorities to guide the potential transition from amphibian declines to recoveries and to maximize conservation efforts. © 2022 The Authors

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Consequences of interspecific variation in defenses and herbivore host choice for the ecology and evolution of Inga, a speciose rainforest tree

2018 , Coley P.D. , Endara M.-J. , Kursar T.A.

We summarize work on a speciose Neotropical tree genus, Inga (Fabaceae), examining how interspecific variation in anti-herbivore defenses may have evolved, how defenses shape host choice by herbivores and how they might regulate community composition and influence species radiations. Defenses of expanding leaves include secondary metabolites, extrafloral nectaries, rapid leaf expansion, trichomes, and synchrony and timing of leaf production. These six classes of defenses are orthogonal, supporting independent evolutionary trajectories. Moreover, only trichomes show a phylogenetic signature, suggesting evolutionary lability in nearly all defenses. The interspecific diversity in secondary metabolite profiles does not arise from the evolution of novel compounds, but from novel combinations of common compounds, presumably due to changes in gene regulation. Herbivore host choice is determined by plant defensive traits, not host phylogeny. Neighboring plants escape each other’s pests if their defenses differ enough, thereby enforcing the high local diversity typical of tropical forests. Related herbivores feed on hosts with similar defenses, implying that there are phylogenetic constraints placed on the herbivore traits that are associated with host use. Divergence in defensive traits among Inga appears to be driven by herbivore pressure. However, the lack of congruence between herbivore and host phylogeny suggests that herbivores are tracking defenses, choosing hosts based on traits for which they already have adaptations. There is, therefore, an asymmetry in the host–herbivore evolutionary arms race. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.

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