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Coloma L.A.,Centro Jambatu Of Investigacion Y Conservacion Of Anfibios | Carvajal-Endara S.,Centro Jambatu Of Investigacion Y Conservacion Of Anfibios | Duenas J.F.,Centro Jambatu Of Investigacion Y Conservacion Of Anfibios | Paredes-Recalde A.,San Francisco de Quito University | And 6 more authors.
Zootaxa | Year: 2012

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.


Proano-Bolanos C.,Queens University of Belfast | Zhou M.,Queens University of Belfast | Wang L.,Queens University of Belfast | Coloma L.A.,Centro Jambatu Of Investigacion Y Conservacion Of Anfibios | And 3 more authors.
Journal of Proteomics | Year: 2016

Phyllomedusine frogs are an extraordinary source of biologically active peptides. At least 8 families of antimicrobial peptides have been reported in this frog clade, the dermaseptins being the most diverse. By a peptidomic approach, integrating molecular cloning, Edman degradation sequencing and tandem mass spectrometry, a new family of antimicrobial peptides has been identified in Cruziohyla calcarifer. These 15 novel antimicrobial peptides of 20-32 residues in length are named cruzioseptins. They are characterized by having a unique shared N-terminal sequence GFLD- and the sequence motifs -VALGAVSK- or -GKAAL(N/G/S) (V/A)V- in the middle of the peptide. Cruzioseptins have a broad spectrum of antimicrobial activity and low haemolytic effect. The most potent cruzioseptin was CZS-1 that had a MIC of 3.77 μM against the Gram positive bacterium, Staphylococcus aureus and the yeast Candida albicans. In contrast, CZS-1 was 3-fold less potent against the Gram negative bacterium, Escherichia coli (MIC 15.11 μM). CZS-1 reached 100% haemolysis at 120.87 μM. Skin secretions from unexplored species such as C. calcarifer continue to demonstrate the enormous molecular diversity hidden in the amphibian skin. Some of these novel peptides may provide lead structures for the development of a new class of antibiotics and antifungals of therapeutic use. Biological significance: Through the combination of molecular cloning, Edman degradation sequencing, tandem mass spectrometry and MALDI-TOF MS we have identified a new family of 15 antimicrobial peptides in the skin secretion of Cruziohyla calcarifer. The novel family is named "Cruzioseptins" and contains cationic amphipathic peptides of 20-32 residues. They have a broad range of antimicrobial activity that also includes effective antifungals with low haemolytic activity. Therefore, C. calcarifer has proven to be a rich source of novel peptides, which could become leading structures for the development of novel antibiotics and antifungals of clinical application. © 2016 Elsevier B.V.


Santos J.C.,University of British Columbia | Santos J.C.,National Evolutionary Synthesis Center | Baquero M.,Mississippi State University | Barrio-Amoros C.,Institute Biodiversidad Tropical | And 4 more authors.
Proceedings of the Royal Society B: Biological Sciences | Year: 2014

Multimodal signals facilitate communication with conspecifics during courtship, but they can also alert eavesdropper predators. Hence, signallers face two pressures: enticing partners to mate and avoiding detection by enemies. Undefended organisms with limited escape abilities are expected to minimize predator recognition over mate attraction by limiting or modifying their signalling. Alternatively, organisms with anti-predator mechanisms such as aposematism (i.e. unprofitability signalled by warning cues) might elaborate mating signals as a consequence of reduced predation. We hypothesize that calls diversified in association with aposematism. To test this, we assembled a large acoustic signal database for a diurnal lineage of aposematic and cryptic/non-defended taxa, the poison frogs. First, we showed that aposematic and non-aposematic species share similar extinction rates, and aposematic lineages diversify more and rarely revert to the nonaposematic phenotype. We then characterized mating calls based on morphological (spectral), behavioural/physiological (temporal) and environmental traits. Of these, only spectral and temporal features were associated with aposematism. We propose that with the evolution of antipredator defences, reduced predation facilitated the diversification of vocal signals, which then became elaborated or showy via sexual selection. © 2014 The Author(s) Published by the Royal Society. All rights reserved.


Santos J.C.,University of British Columbia | Baquero M.,Mississippi State University | Barrio-Amoros C.,Institute Biodiversidad Tropical | Coloma L.A.,Centro Jambatu Of Investigacion Y Conservacion Of Anfibios | And 3 more authors.
Proceedings. Biological sciences / The Royal Society | Year: 2014

Multimodal signals facilitate communication with conspecifics during courtship, but they can also alert eavesdropper predators. Hence, signallers face two pressures: enticing partners to mate and avoiding detection by enemies. Undefended organisms with limited escape abilities are expected to minimize predator recognition over mate attraction by limiting or modifying their signalling. Alternatively, organisms with anti-predator mechanisms such as aposematism (i.e. unprofitability signalled by warning cues) might elaborate mating signals as a consequence of reduced predation. We hypothesize that calls diversified in association with aposematism. To test this, we assembled a large acoustic signal database for a diurnal lineage of aposematic and cryptic/non-defended taxa, the poison frogs. First, we showed that aposematic and non-aposematic species share similar extinction rates, and aposematic lineages diversify more and rarely revert to the non-aposematic phenotype. We then characterized mating calls based on morphological (spectral), behavioural/physiological (temporal) and environmental traits. Of these, only spectral and temporal features were associated with aposematism. We propose that with the evolution of anti-predator defences, reduced predation facilitated the diversification of vocal signals, which then became elaborated or showy via sexual selection. © 2014 The Author(s) Published by the Royal Society. All rights reserved.


McGugan J.R.,Harvard University | Byrd G.D.,Harvard University | Roland A.B.,Harvard University | Caty S.N.,Harvard University | And 6 more authors.
Journal of Chemical Ecology | Year: 2016

Poison frogs sequester chemical defenses from arthropod prey, although the details of how arthropod diversity contributes to variation in poison frog toxins remains unclear. We characterized skin alkaloid profiles in the Little Devil poison frog, Oophaga sylvatica (Dendrobatidae), across three populations in northwestern Ecuador. Using gas chromatography/mass spectrometry, we identified histrionicotoxins, 3,5- and 5,8-disubstituted indolizidines, decahydroquinolines, and lehmizidines as the primary alkaloid toxins in these O. sylvatica populations. Frog skin alkaloid composition varied along a geographical gradient following population distribution in a principal component analysis. We also characterized diversity in arthropods isolated from frog stomach contents and confirmed that O. sylvatica specialize on ants and mites. To test the hypothesis that poison frog toxin variability reflects species and chemical diversity in arthropod prey, we (1) used sequencing of cytochrome oxidase 1 to identify individual prey specimens, and (2) used liquid chromatography/mass spectrometry to chemically profile consumed ants and mites. We identified 45 ants and 9 mites in frog stomachs, including several undescribed species. We also showed that chemical profiles of consumed ants and mites cluster by frog population, suggesting different frog populations have access to chemically distinct prey. Finally, by comparing chemical profiles of frog skin and isolated prey items, we traced the arthropod source of four poison frog alkaloids, including 3,5- and 5,8-disubstituted indolizidines and a lehmizidine alkaloid. Together, the data show that toxin variability in O. sylvatica reflects chemical diversity in arthropod prey. © 2016 Springer Science+Business Media New York

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