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1.
J Nat Prod ; 86(7): 1761-1769, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37219414

RESUMO

Amphibians' skin is a rich source of natural antimicrobial peptides (AMPs). These AMPs exhibit marked inter- and intraspecific sequence divergence linked to the arms race between host and pathogens. Here, we combine peptidomics, molecular modeling, and phylogenetic analyses to understand the evolution of AMPs in Cophomantini, a diverse clade of neotropical tree frogs, and to investigate their interaction with bacterial membranes. Consistent with results in other amphibians, all species of Cophomantini secrete a mixture of peptides. We selected the hylin peptide family to survey sequence variability and the presence of common amino acid motifs. We found that most species secrete a unique set of hylins that, though variable, share the conserved motif Gly-X-X-X-Pro-Ala-X-X-Gly, with Gly and Pro colocalizing with charged or polar residues. Our modeling revealed that Pro curves the peptide through a hinge, facilitating its insertion into the bacterial membrane and, once inserted, contributes to stabilizing the pore structure. The phylogenetic inference using hylid prepro-peptides showed the need to classify new AMPs using the full-length sequence of the prepro-peptide region and highlighted the complex relationships between peptide families. Our findings revealed that conserved motifs occurred independently in distinct AMP families, suggesting a convergent evolution and a significant role in peptide-membrane interactions.


Assuntos
Peptídeos Antimicrobianos , Peptídeos , Humanos , Animais , Sequência de Aminoácidos , Filogenia , Peptídeos/química , Anuros/metabolismo
2.
Zootaxa ; 5040(3): 334-364, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34811037

RESUMO

Frequent biodiversity sampling and monitoring programs often lead to relevant taxonomic findings. Here, as a product of different field expeditions to two places in the northern Andes, we discover and describe two new species of rain frogs of the genus Pristimantis from the cloud forests of the Central Cordillera of Colombia. Pristimantis chocolatebari sp. nov. is diagnosed by having the following character states: dentigerous process of vomer triangular, snout large and protruding, dorsum smooth, vocal slits and vocal sac present, groin and hidden part of the thighs yellow. Pristimantis carylae sp. nov. is diagnosed by having iris copper red, dentigerous process of vomer oval, snout short and rounded, dorsum finely shagreen with scattered tubercles, double nuptial pad in males, groin and hidden part of thighs pink. We also infer, for the first time, the phylogenetic position of P. permixtus, P. platychilus, and two candidate new species. In addition, we emphasize not to use genetic distance as the only source of evidence for species delimitation, considering the high intraspecific diversity found in one of the species described here. Finally, we highlight the relevance of different habitat and ecosystem conservation strategies to promote amphibian diversity studies in the Andes.


Assuntos
Anuros , Ecossistema , Filogenia , Animais , Anuros/genética , Biodiversidade , Colômbia , Feminino , Masculino
3.
Cladistics ; 37(1): 73-105, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-34478175

RESUMO

The relationships of the hyline tribe Dendropsophini remain poorly studied, with most published analyses dealing with few of the species groups of Dendropsophus. In order to test the monophyly of Dendropsophini, its genera, and the species groups currently recognized in Dendropsophus, we performed a total evidence phylogenetic analysis. The molecular dataset included sequences of three mitochondrial and five nuclear genes from 210 terminals, including 12 outgroup species, the two species of Xenohyla, and 93 of the 108 recognized species of Dendropsophus. The phenomic dataset includes 46 terminals, one per species (34 Dendropsophus, one Xenohyla, and 11 outgroup species). Our results corroborate the monophyly of Dendropsophini and the reciprocal monophyly of Dendropsophus and Xenohyla. Some species groups of Dendropsophus are paraphyletic (the D. microcephalus, D. minimus, and D. parviceps groups, and the D. rubicundulus clade). On the basis of our results, we recognize nine species groups; for three of them (D. leucophyllatus, D. microcephalus, and D. parviceps groups) we recognize some nominal clades to highlight specific morphology or relationships and facilitate species taxonomy. We further discuss the evolution of oviposition site selection, where our results show multiple instances of independent evolution of terrestrial egg clutches during the evolutionary history of Dendropsophus.


Assuntos
Anuros/classificação , Anuros/genética , Filogenia , Animais , Núcleo Celular/genética , Genes Mitocondriais , RNA Ribossômico 16S , Análise de Sequência de DNA
4.
Zootaxa ; 4979(1): 5769, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34187014

RESUMO

Zootaxa is a mega-journal that since its inception, 20 years ago, has contributed to the documentation of the planet's biodiversity. Its role concerning terrestrial vertebrates has been crucial especially for amphibians, which are the most threatened class of vertebrates. As current editors of the Amphibia section, we reviewed the state of knowledge of taxonomic publications on amphibians over the last two decades (from 2001 to 2020). Our review reveals that 2,533 frogs, 259 salamanders, and 55 caecilians have been named in these 20 years, mainly in the tropical regions of South America, Asia, and Africa. More than half (57%) of these species descriptions were published in only 10 journals. At least 827 species of the new amphibians (29% of the total) were described in Zootaxa. This mega-journal has served also as a place of publication for monographs and systematic reviews, in addition to short articles documenting the vocalizations of anurans and the morphology of embryos and larvae. Its efficient evaluation process, the freedom of manuscript length, including full-color figures, and free of cost for the authors, has made Zootaxa a favorite for amphibian researchers. In an era of accelerating rates of biodiversity loss, documenting, describing, naming, and proposing evolutionary scenarios for species is, more than ever, an urgent task.


Assuntos
Anfíbios/classificação , Animais , Anuros/classificação , Publicações Periódicas como Assunto , Urodelos/classificação
5.
Zootaxa ; 4838(1): zootaxa.4838.1.4, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-33056833

RESUMO

Continuous sampling in well studied areas may lead to new amphibian species discoveries, because population dynamics allow rare species to go unnoticed for years. Based on recent sampling of frogs in the northeastern region of Colombia, here we provide genetic, morphological, and bioacoustics evidence to support the description of a new species of the genus Pristimantis. Phylogenetic analysis suggests the new species is a member of the P. lacrimosus species group, a clade of 25 species that is highly diverse in Ecuador and Peru. This new species is more closely related to allopatric species from Peru and Guyana (i.e. P. olivaceus, P. pluvialis, P. pulchridormientes, and an undetermined Pristimantis). The new species has green-yellow coloration and a remarkable brown interocular band, which is unusual in the genus and which inspired the epithet. Pristimantis zorro sp. nov. has only been found at one locality at 1860 m s.a.l., on the eastern flank of the northern Cordillera Central in Department of Antioquia, Colombia. The new species inhabits the ecotone between the humid cloud forest and open areas. Repeated visits to the type locality suggest high variation in population abundance and/or species detection, because we have occasionally observed many individuals in briefs periods of times. In addition, we discuss the biogeographical and systematic implications of our species discovery.


Assuntos
Anuros , Animais , Colômbia , Filogenia
6.
Zootaxa ; 4532(3): 441-443, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30647359

RESUMO

Nyctimantis rugiceps Boulenger, 1882 (Fig. 1A) is a Neotropical treefrog (Duellman Trueb 1976; Faivovich et al. 2005) known only from disjunct localities in Amazonian Colombia, Ecuador, and Peru (Pérez-Villota et al. 2009). This species has the skin of the skull co-ossified and reproduces-including calling behavior, egg deposition and tadpole development-in water-filled tree or bamboo cavities (Duellman Trueb 1976; Duellman 1978). Given its secretive behavior, this is a poorly known species and, as noted by Duellman (1978: 169), "the major clue to the life history of Nyctimantis is the calling behavior of the males". Unfortunately, the only quantitative description of the advertisement call of N. rugiceps is a brief passage in Duellman (1978) based on four specimens from Santa Cecilia, Ecuador, where important variables are missing (e.g., call duration). More importantly, graphs illustrating the waveform and spectrogram are missing. Considering these limitations and the importance of advertisement calls to the study of anurans (Köhler et al. 2017), we provide a quantitative description using a call recording obtained in Leticia, Amazonas, Colombia.


Assuntos
Anuros , Vocalização Animal , Animais , Colômbia , Equador , Masculino , Peru
8.
Zootaxa ; 4242(2): 313-343, 2017 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-28610186

RESUMO

Pristimantis, distributed throughout the New World tropics, is the most speciose vertebrate genus. Pristimantis presents an enormous morphological diversity and is currently divided into several demonstrably non-monophyletic phenetic species groups. With the purpose of increasing our understanding of Pristimantis systematics, we present the first phylogenetic analysis using molecular evidence to test the monophyly and infer evolutionary relationships within the Pristimantis leptolophus group, an endemic group of frogs from the highlands of the Colombian Andes. Our phylogenetic reconstruction recovers the group as monophyletic with high support, indicating general concordance between molecular data and morphological data. In addition, we describe a new polymorphic species lacking conspicuous tubercles, a regular attribute among species of the P. leptolophus species group and endemic from the Páramo de Sonsón complex (Antioquia, Colombia). The phylogenetic position of the new species is inferred and other systematic implications in the light of our results are discussed.


Assuntos
Anuros , Animais , Evolução Biológica , Filogenia
9.
Zootaxa ; 4061(1): 29-40, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27395477

RESUMO

We describe a remarkable new species of monophyletic genus Hyloscirtus from northeastern Peru. The presence of an enlarged, curved, and protruding prepollical spine; hypertrophied forelimbs; large, thick supracloacal flap and supratympanic fold; large size; nuptial pad absent and iris dark red diagnose this species. We hypothesize that the new species is closely related to H. condor and H. tapichalaca of southern Ecuador due to the apparently synapomorphic occurrence in these species of an enlarged, curved prepollical spine, and small, conical vomerine odontophore processes with 3-6 prominent teeth each without contact between these. Additional research explicitly incorporating H. diabolus new species in a phylogenetic analysis is required to further test our hypothesis and provide a better understanding of the evolution of morphological attributes described herein. Finally we discuss some aspects concerning the taxonomy of the genus Hyloscirtus.


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/genética , Anuros/crescimento & desenvolvimento , Tamanho Corporal , Masculino , Tamanho do Órgão , Peru , Filogenia
10.
Zootaxa ; 3900(2): 223-42, 2014 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-25543734

RESUMO

We describe a new species of Pristimantis from the humid forests on the eastern flank of the northern Cordillera Central in Colombia (6º 23' 19.3554" N, 75º 1' 24.0594" W; ca. 1150 m.a.s.l.). Pristimantis jaguensis sp. nov. is characterized by an extraordinary variation in color and is readily distinguished from congeneric species by lacking nuptial pads, discoidal fold and conical calcar tubercles; flanks and belly white to cream without blotches as well as iris yellow ocher to copper with thick brown reticulation and cream sclera. Molecular phylogenetic analyses recovered the new species in a clade with species mostly distributed in Ecuador. Our finding suggests that new taxa can still be discovered in the Middle Magdalena River valley of Colombia despite the extensive sampling this region has received during the last decades. 


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/genética , Anuros/crescimento & desenvolvimento , Tamanho Corporal , Colômbia , Ecossistema , Equador , Feminino , Masculino , Tamanho do Órgão , Filogenia
12.
Zootaxa ; 3686: 447-60, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26473232

RESUMO

We describe Dendropsophus manonegra sp. nov. from the upper Amazon basin in the eastern foothills of the Andes in Colombia (1 degree 47' 42.2" N, 75 degrees 38' 48.7" W; 1040 m a.s.l.). Phylogenetic analysis of DNA sequences of 2582 aligned base pairs of the 12S and 16S rRNA genes recovered the new species as a member of the D. leucophyllatus species group and sister to D. bifurcus. Morphological traits, such as the presence of pectoral glands in males and females, support this hypothesis. The new species is readily distinguished from all other members of the species group by having bluish-black coloration on fingers, toes, webbing, axillary membranes, groin and hidden surfaces of arms and legs. Some aspects on the composition and systematics of the D. leucophyllatus group are discussed.


Assuntos
Anuros/classificação , Anuros/genética , Filogenia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/crescimento & desenvolvimento , Tamanho Corporal , Colômbia , Cor , Ecossistema , Feminino , Masculino
13.
Zootaxa ; 3636: 85-100, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26042285

RESUMO

We describe a new species of the charismatic red-eyed treefrogs (genus Agalychnis) from middle Magdalena River valley of Colombia (05°50'8.04"N, 74°50'16.55"W, 380 m a.s.l.). The new species is readily distinguished from all species members of the group by having orange flanks with small white warts. Phylogenetic analysis of DNA sequences of 16S rRNA gene recovered the new species as a member of the Agalychnis callidryas group. The presence of a red hue in the iris and a golden reticulated palpebral membrane, putative synapomorphies of the clade, support this hypothesis. Our analysis suggests that Agalychnis terranova sp. nov is closely related to A. callidryas from Central America and is proposed as its sister species with an uncorrected genetic distance of 5.69% between these taxa. The phylogenetic position and the geographic distribution of the new taxon add new lights to the presence of a biogeographic disjunction between Middle America lowlands, the Pacific region and Magdalena River valley of Colombia.


Assuntos
Anuros/classificação , Filogenia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/genética , Anuros/crescimento & desenvolvimento , Colômbia , Ecossistema , Feminino , Masculino , Tamanho do Órgão , Rios
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