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1.
Am Nat ; 198(4): 522-539, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34559606

RESUMO

AbstractUnrelated species often evolve similar phenotypic solutions to the same environmental problem, a phenomenon known as convergent evolution. But how do these common traits arise? We address this question from a physiological perspective by assessing how convergence of an elaborate gestural display in frogs (foot-flagging) is linked to changes in the androgenic hormone systems that underlie it. We show that the emergence of this rare display in unrelated anuran taxa is marked by a robust increase in the expression of androgen receptor (AR) messenger RNA in the musculature that actuates leg and foot movements, but we find no evidence of changes in the abundance of AR expression in these frogs' central nervous systems. Meanwhile, the magnitude of the evolutionary change in muscular AR and its association with the origin of foot-flagging differ among clades, suggesting that these variables evolve together in a mosaic fashion. Finally, while gestural displays do differ between species, variation in the complexity of a foot-flagging routine does not predict differences in muscular AR. Altogether, these findings suggest that androgen-muscle interactions provide a conduit for convergence in sexual display behavior, potentially providing a path of least resistance for the evolution of motor performance.


Assuntos
Comportamento Sexual Animal , Animais , Anuros/genética , Evolução Biológica , Expressão Gênica , Fenótipo
2.
Zootaxa ; 4834(3): zootaxa.4834.3.3, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-33056114

RESUMO

We examine the phylogenetic relationships among salamanders of the genus Bolitoglossa (Eladinea) distributed in the Amazonian basin of northern Peru and southern Ecuador and assess species diversity based on morphological and phylogenetic analyses. We infer a molecular phylogeny using sequences from two mitochondrial (Cytb, 16S) and two nuclear genes (RAG-1, POMC). We find two well-supported subclades, one including [B. altamazonica + B. peruviana] + B. awajun sp. n., and the other including Bolitoglossa sp. Ituxi + Bolitoglossa sp. Jurúa. Ecuadorian lineages form divergent clades from the Peruvian lineages. Accordingly, Ecuadorian populations previously assigned to Bolitoglossa peruviana sensu lato are treated as members of a Bolitoglossa equatoriana species complex. A newly defined Bolitoglossa altamazonica species complex contains only populations from the Amazonian rainforest of Peru. Maximum likelihood and Bayesian Inference analyses confirm the phylogenetic placement of B. altamazonica and B. peruviana, and support recognition of a related new species of Bolitoglossa. The uncorrected genetic distances between the new species and B. altamazonica are 6.5% for Cytb and 4.9% for 16S; and the uncorrected genetic distances between the new species and B. peruviana are 8.0% for Cytb and 3.9% for 16S. Additionally, analyses of nuclear gene sequences show no haplotype sharing between the new species and closely related species. The new species is distinguished from its congeners by a combination of the following morphological characters: (1) Standard length mean 37.7 mm in males (range 32.0-42.2; n=5) and 41.4 mm in females (range 34.9-48.2; n=6); (2) in life, dorsal coloration uniformly brown with a dark brown triangular marking between the eyes or some irregular light cream spots or patches on the head, back and flanks; (3) iris pale golden; (4) in preservative, dark brown venter with cream mottlings or moderate-sized blotches on the gular region, belly, cloacal region and tail; (5) tips of third finger and third toe protuberant and pointed with nearly complete webbing on the hands and feet; (6) 11-26 maxillary teeth and 8-24 vomerine teeth. Given that the syntypes of B. altamazonica are lost, we designate a neotype for B. altamazonica from Allpahuayo Mishana National Reserve, Loreto department, Peru. Newly collected specimens from ~30 km NE from Moyobamba (type locality of B. peruviana) provide a better understanding of B. peruviana and enable us to show that it is the sister taxon of B. altamazonica. The new species is known from pre-montane forests in Cordillera Escalera Regional Conservation Area, Cordillera Azul National Park and Shucshuyacu, San Martin department, Peru at 485-1311 m elevation,  ~75 km SE from Moyobamba. Bolitoglossa awajun sp. n. is the fourth endemic species of salamander from Peru.


Assuntos
Urodelos , Animais , Teorema de Bayes , Feminino , Masculino , Peru , Filogenia
5.
Zootaxa ; 4338(1): 195-200, 2017 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-29245736

RESUMO

Phrynopus montium (Shreve, 1938) was described from Cascas, Junín Department, Peru, at an undetermined elevation between 3000 and 4000 m a.s.l. in the Cordillera Central. With the exception of the type specimens used in the original description, no additional sightings of P. montium had been reported for 76 years. Additionally, its coloration in life, microhabitat use, and precise elevational distribution remained unknown. During a field expedition conducted in 2014, two individuals of P. montium were found at an upper cloud forest site in central Peru, 8.7 km south from Hacienda Cascas. Here, I describe the coloration in life, microhabitat use, and elevation of these individuals.


Assuntos
Anuros , Animais , Florestas , Peru
6.
Zootaxa ; 4221(1): zootaxa.4221.1.3, 2017 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-28187674

RESUMO

We describe and name a new species of poison-dart frog from the Amazonian slopes of the Andes in Manu Province, Madre de Dios Department, Peru; specifically within the Amarakaeri Communal Reserve and the buffer zone of Manu National Park. Ameerega shihuemoy sp. nov. is supported by a unique combination of characters: black dorsum with cream to light orange dorsolateral lines, blue belly reticulated with black, and the lack of axillary, thigh and calf flash marks. Within Ameerega, it shares the general appearance of A. altamazonica, A. boliviana, A. hahneli, A. ignipedis, A. petersi, A. picta, A. pongoensis, A. pulchripecta, A. simulans, A. smaragdina, and A. yungicola; each possessing a granular black to brown dorsum, a light labial bar, a conspicuous dorsolateral line running from the snout to the groin, and a metallic blue belly and underside of arms and hind limbs. From most of these species it can be distinguished by lacking flash marks on the axillae, thighs, and calves (absent in only A. boliviana and A. smaragdina, most A. petersi, and some A. pongoensis), by having bright cream to orange dorsolateral stripes (white, intense yellow, or green in all other species, with the exception of A. picta), and by its blue belly reticulated with black (bluish white and black in A. boliviana, green and blue with black marbling in A. petersi, and green and blue lacking black marbling in A. smaragdina). Its mating call also shows clear differences to morphologically similar species, with a lower note repetition rate, longer space between calls, and higher fundamental and dominant frequencies. Phylogenetic analyses based on the 16S mitochondrial rRNA fragment also support the distinctiveness of the new species and suggest that A. shihuemoy is most closely related to Ameerega macero, A. altamazonica, A. rubriventris, and two undescribed species (Ameerega sp. from Porto Walter, Acre, Brazil, and Ameerega sp. from Ivochote, Cusco, Peru). Genetically, the new species is most similar to the sympatric A. macero, from which it clearly differs in characteristics of its advertisement call and coloration. The new species is found near rocky streams during the dry season and near temporary water bodies during the rainy season. Tadpoles are found in lentic water along streams, or in shallow, slow-moving streams. Given its small geographic range, we recommend that A. shihuemoy should be considered 'Near threatened' (NT) according to IUCN Red List criteria.


Assuntos
Anuros , Filogenia , Vocalização Animal , Animais , Brasil , Peru , Venenos
7.
Biota neotrop. (Online, Ed. port.) ; 13(4): 269-283, Oct-Dec/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-703580

RESUMO

We compile a list of all amphibians and reptiles known to occur within Manu National Park, Peru and its buffer zone, located in one of the world's biodiversity hotspots. Covering approximately 0.01% of the planet's terrestrial surface, this protected area preserves 155 species of amphibians and 132 species of reptiles, corresponding to 2.2% and 1.5% respectively of the known diversity for these groups. Moreover, Manu National Park preserves natural habitats and populations of one critically endangered (Atelopus erythropus), three endangered (Bryophryne cophites, Pristimantis cosnipatae and Psychrophrynella usurpator), three vulnerable amphibians (Atelopus tricolor, Gastrotheca excubitor, Rhinella manu) and two vulnerable reptiles (Chelonoidis denticulata, Podocnemis unifilis), according to the threat categories of the IUCN Red List.


Producimos una lista de las especies de anfibios y reptiles conocidas del Parque Nacional del Manu, Perú y su zona de amortiguamiento, ubicados en unas de las regiones con más biodiversidad en el planeta. El área protegida cubre tan solo cerca del 0.01% de la superficie terrestre mundial, sin embargo conserva a 155 especies de anfibios y 132 especies de reptiles, lo cual corresponde al 2.2% de todos los anfibios y al 1.5% de todos los reptiles conocidos. Además, el Parque Nacional del Manu protege los hábitats y las poblaciones de una especie críticamente amenazada (Atelopus erythropus), tres especies amenazadas (Bryophryne cophites, Pristimantis cosnipatae y Psychrophrynella usurpator), tres especies vulnerables de anfibios (Atelopus tricolor, Gastrotheca excubitor, Rhinella manu), y dos especies vulnerables de reptiles (Chelonoidis denticulata, Podocnemis unifilis), de acuerdo a las categorías de amenaza de la Lista Roja de la UICN.

8.
Mol Phylogenet Evol ; 41(1): 149-64, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16815043

RESUMO

Amazonia is famous for high biodiversity, and the highlands of the transition zone between the Andes and the lowlands of the Amazon basin show particularly high species diversity. Hypotheses proposed to explain the high levels of diversity in the highlands include repeated parapatric speciation across ecological gradients spanning the transition zone, repeated allopatric speciation across geographic barriers between the highlands and lowlands, divergence across geographic barriers within the transition zone, and simple lineage accumulation over long periods of time. In this study, we investigated patterns of divergence in frogs of the genus Epipedobates (family Dendrobatidae) using phylogenetic and biogeographic analyses of divergence in mitochondrial DNA (1778 aligned positions from genes encoding cyt b, 12S and 16S rRNA for 60 Epipedobates and 11 outgroup specimens) and coloration (measured for 18 specimens representing nine species in Epipedobates). The majority of phenotypic and species diversity in the poison frog genus Epipedobates occurs in the transition zone, although two morphologically conserved members of the genus are distributed across the lowlands of the Amazon basin. Phylogenetic analysis reveals that there is a single highland clade derived from an ancestral colonization event in northern Peru by a population of lowland ancestry. Epipedobates trivittatus, a widespread Amazonian species, is a member of the highland clade that reinvaded the lowlands. Comparative analyses of divergence in coloration and mtDNA reveals that divergence in coloration among populations and species in the highlands has been accelerated relative to the lowlands. This suggests a role for selection in the divergence of coloration among populations and species.


Assuntos
Anuros/genética , Variação Genética , Genética Populacional , Filogenia , Animais , Anuros/fisiologia , Citocromos b/genética , Peru , RNA Ribossômico , RNA Ribossômico 16S , Seleção Genética
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