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1.
Zootaxa ; 4951(2): zootaxa.4951.2.1, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33903400

RESUMO

Allobates trilineatus is the second most geographically widespread species in the genus Allobates, its range extending from northern Ecuador to southern Peru along the Andean foothills of Amazonia and to the east, into Acre, Brazil. However, detailed phenotypic and genetic variation from topotypic specimens is lacking, raising doubts about the identification of specimens in the literature. To solve this problem, we collected 16 topotypic specimens-including male and female adults and juveniles-and associated data such as advertisement calls and tissue samples. Based upon this material, we redescribe the phenotypic variation within A. trilineatus and evaluate its phylogenetic position using a fragment of the mitochondrial gene 16S rDNA. Allobates trilineatus is distinguished from its congeners by its small body size (adult snout-to-vent-length = 14.6-16.6 mm), preserved males with dark gray throat, and gray chest and belly, pale dorsolateral stripe straight and conspicuous, and advertisement call formed by the emission of groups of note-pairs with dominant frequency at 5.06-5.81 kHz. Our phylogenetic results indicate that none of the specimens assigned to this species in previous phylogenetic studies cluster within the clade formed by topotypic samples, except for the sample of one tadpole. Furthermore, our comparison of published phenotypic and genetic data assigned to A. trilineatus with our new data led us to conclude that A. trilineatus as previously recognized was actually a complex of cryptic, closely related species. Although with the data at hand we cannot fully resolve the taxonomy of all sampled populations in previous studies, we provide a new definition and delimitation of A. trilineatus sensu stricto, assign other specimens to different evolutionary units corresponding to candidate species, and flag other important taxonomic issues.


Assuntos
Anuros , Animais , Anuros/classificação , Anuros/genética , Feminino , Masculino , Filogenia
2.
Zootaxa ; 4869(1): zootaxa.4869.1.6, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33311374

RESUMO

We quantitatively describe for the first time the advertisement call of Chiasmocleis (Syncope) carvalhoi using recordings  of five specimens from northern Peruvian Amazonia. The advertisement call is characterized by a single, short, tonal, and high-pitched note. Call duration ranges between 0.03-0.06 s and its dominant frequency between 7.12-7.92 kHz. The lack of pulses within notes distinguishes C. (Syncope) carvalhoi from all congeneric species except C. (Syncope) antenori, C. (Syncope) parkeri and C. (Chiasmocleis) mantiqueira, which can be distinguished by the shorter duration of their notes and silent intervals (in C. (Syncope) antenori and C. (Syncope) parkeri) and by the lower dominant frequency (in C. (Syncope) parkeri and C. (Chiasmocleis) mantiqueira). In addition, based on our collected specimens, we report on and discuss about the variation of some external morphological characters and natural history of C. (Syncope) carvalhoi, including the absence of vocal slits and sacs. Our study reveals a potential association between the absence of vocal slits and sacs, and tonal calls in Chiasmocleis, as well as conflicting morphological diagnostics characters in the literature.


Assuntos
Anuros , Vocalização Animal , Animais , Brasil , Peru
3.
Heredity (Edinb) ; 124(3): 439-456, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31712747

RESUMO

While intraspecific variation in aposematic signals can be selected for by different predatory responses, their evolution is also contingent on other processes shaping genetic variation. We evaluate the relative contributions of selection, geographic isolation, and random genetic drift to the evolution of aposematic color polymorphism in the poison frog Adelphobates galactonotus, distributed throughout eastern Brazilian Amazonia. Dorsal coloration was measured for 111 individuals and genetic data were obtained from 220 individuals at two mitochondrial genes (mtDNA) and 7963 Single Nucleotide Polymorphisms (SNPs). Four color categories were described (brown, blue, yellow, orange) and our models of frog and bird visual systems indicated that each color was distinguishable for these taxa. Using outlier and correlative analyses we found no compelling genetic evidence for color being under divergent selection. A time-calibrated mtDNA tree suggests that the present distribution of dorsal coloration resulted from processes occurring during the Pleistocene. Separate phylogenies based on SNPs and mtDNA resolved the same well supported clades, each containing different colored populations. Ancestral character state analysis provided some evidence for evolutionary transitions in color type. Genetic structure was more strongly associated with geographic features, than color category, suggesting that the distribution of color is explained by localized processes. Evidence for geographic isolation together with estimates of low effective population size implicates drift as playing a key role in color diversification. Our results highlight the relevance of considering the neutral processes involved with the evolution of traits with important fitness consequences.


Assuntos
Anuros/genética , Deriva Genética , Pigmentação , Seleção Genética , Animais , Brasil , Genes Mitocondriais , Filogenia , Pigmentação/genética , Polimorfismo de Nucleotídeo Único
4.
Acta amaz ; 49(4): 307-310, out. - dez. 2019.
Artigo em Inglês | LILACS | ID: biblio-1118953

RESUMO

Although relatively common among omnivorous primates, anurophagy is still poorly documented in frugivorous species. Here we report the predation of a giant gladiator treefrog (Boana boans) by a large arboreal frugivore, the gray woolly monkey (Lagothrix lagotricha cana). The predation event occurred in a stretch of riparian forest located in a fragmented region in Cacoal, Rondônia state, in southwestern Brazilian Amazonia. Anurans can be a profitable, non-contested, and relatively easily acquired alternative resource for gray woolly monkeys, helping to fulfill their demand for protein, especially in periods of fruit scarcity. This new record broadens the knowledge on the natural history and predators of the giant gladiator frog. (AU)


Assuntos
Anuros , Primatas , Ecossistema Amazônico , Dieta , Atelinae
5.
Zootaxa ; 4550(1): 71-100, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30790877

RESUMO

We describe a new species of nurse-frog (Aromobatidae, Allobates) from Floresta Nacional de Carajás, southeastern Brazilian Amazonia. Allobates carajas sp. nov. is distinguished from similar congeneric species by the combination of the following characters: body-size range (snout-to-vent length 16.5-19.1 mm), dorsal color pattern with a dark brown hourglass-shaped mark, by the absence of a pale dorsolateral stripe and presence of a pale ventrolateral stripe, absence of a pale paracloacal mark, by overall bright yellow ventral colors of live male and female specimens, and by the posterior labium of tadpoles, with a single row of pyramidal papillae medially. The advertisement call of the new species is highly variable, with four possible temporal arrangements of notes (continuous emission of notes separated by regular silent intervals, continuous emission of notes separated by irregular silent intervals, emission of discrete note trills, and sporadic emission of single notes). Duration of notes range between 0.020-0.060 s, and the dominant frequency of notes range from 4.75 to 5.38 kHz. The new species is currently known only from forested habitats within Floresta Nacional de Carajás.


Assuntos
Anuros , Ecossistema , Animais , Tamanho Corporal , Brasil , Feminino , Larva , Masculino
6.
Zootaxa ; 4387(1): 109-133, 2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29690488

RESUMO

We describe a new species of nurse-frog (Aromobatidae, Allobates) from northwestern Brazilian Amazon. Allobates juami sp. nov. is distinguished from similar congeneric species by the combination of the following characters: body-size range (snout-to-vent length 17.5-18.5 mm), lack of dark pigments on ventral surfaces of male specimens, dorsal color pattern (predominantly solid dark brown, but conspicuously light brown over snout and urostyle regions), presence of conspicuous pale dorsolateral and ventrolateral stripes, and presence of a diffuse pale paracloacal mark. The advertisement call of the new species lasts 2.5-5.1 s, contains 60-73 short notes (trills), and is emitted at an average rate of 13 notes per second within trills. Duration of silent intervals between notes ranges between 0.020-0.050 s, and the peak frequency of notes ranges from 4.59 to 5.47 kHz. The new species is currently known only from the type locality at Estação Ecológica Juami-Japurá (1.96455° S, 67.93579° W; ~ 87 m a.s.l.).


Assuntos
Anuros , Animais , Tamanho Corporal , Brasil , Masculino , Rios , Vocalização Animal
7.
Zootaxa ; 4532(2): 203-230, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30647363

RESUMO

We describe and name the second species of Phyzelaphryne (Brachycephaloidea, Eleutherodactylidae), from northwestern Brazilian Amazonia. Phyzelaphryne nimio sp. nov. is distinguished from its only congener, Phyzelaphryne miriamae, by its smaller body size and the anatomy of the carpal and metacarpal regions, with relatively larger (sometimes fused) supernumerary carpal and metacarpal tubercles. Molecular phylogenetic analyses based on fragments of the mitochondrial genes 16S rRNA and COI suggest that the currently known distribution of the species is restricted to its type locality and other areas within Estação Ecológica Juami-Japurá, state of Amazonas, Brazil. Based on molecular, morphological and bioacoustic evidence, we assigned other specimens recently collected in Parque Nacional do Jaú, state of Amazonas, Brazil, to P. miriamae, extending the species' known geographic distribution north of the Amazon River.


Assuntos
Anuros , Rios , Animais , Anuros/genética , Brasil , Filogenia , RNA Ribossômico 16S
8.
Evolution ; 71(4): 1039-1050, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28067425

RESUMO

Predation risk is allegedly reduced in Batesian and Müllerian mimics, because their coloration resembles the conspicuous coloration of unpalatable prey. The efficacy of mimicry is thought to be affected by variation in the unpalatability of prey, the conspicuousness of the signals, and the visual system of predators that see them. Many frog species exhibit small colorful patches contrasting against an otherwise dark body. By measuring toxicity and color reflectance in a geographically variable frog species and the syntopic toxic species, we tested whether unpalatability was correlated with between-species color resemblance and whether resemblance was highest for the most conspicuous components of coloration pattern. Heterospecific resemblance in colorful patches was highest between species at the same locality, but unrelated to concomitant variation in toxicity. Surprisingly, resemblance was lower for the conspicuous femoral patches compared to the inconspicuous dorsum. By building visual models, we further tested whether resemblance was affected by the visual system of model predators. As predicted, mimic-model resemblance was higher under the visual system of simulated predators compared to no visual system at all. Our results indicate that femoral patches are aposematic signals and support a role of mimicry in driving phenotypic divergence or mimetic radiation between localities.


Assuntos
Anuros/fisiologia , Evolução Biológica , Mimetismo Biológico , Pigmentação , Distribuição Animal , Animais , Cor , Cadeia Alimentar , Comportamento Predatório
9.
Zootaxa ; 4083(4): 501-25, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-27394243

RESUMO

I describe the seventh species of nurse-frog (Allobates) from the Madeira River basin in Brazilian Amazonia. The new species is distinguished from similar congeneric species by its small body size (snout-to-vent length ranging between 14.0-14.7 mm in adult males and between 14.7-14.9 mm in adult females), by the absence of dark brown regular shapes (e.g. hourglass, "X" or polygon-like marks) on the dorsum, by the absence of transverse dark bars on the dorsal surface of the thigh, and by the light gray to white ventral surfaces, light to dark gray only on throat in live male and female specimens. Males have a distinctive advertisement call characterized by the emission of long (7-11 s) trills of short notes (0.04 s in average) with dominant frequency at 5.9-6.3 kHz and emission rate ranging between 6.7-8.7 notes/s. DNA barcode analyses based on a fragment of the 16S rDNA mitochondrial gene provides additional support to the recognition of the new taxon, which is probably distributed on the east riverbank of the Madeira River, in the interfluve between the Aripuanã and Ji-Paraná rivers.


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/crescimento & desenvolvimento , Anuros/fisiologia , Tamanho Corporal , Brasil , DNA Ribossômico/genética , Ecossistema , Feminino , Genes Mitocondriais , Masculino , Tamanho do Órgão , Filogenia , Rios , Vocalização Animal
10.
Zootaxa ; 3980(4): 501-25, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26249969

RESUMO

We describe the fourth species of nurse-frog genus Allobates occurring in the southeastern Brazilian Amazonia. The new species is sympatric with Allobates femoralis, Allobates masniger and Allobates magnussoni, and inhabits the margins of streams in forested areas within Parque Nacional da Amazônia, on the western bank of the Tapajós River. Snout-to-vent length ranges between 14.9-16.1 mm among males and 15.6-16.5 mm among females. The species is distinguished by the light brown background color of dorsum, with irregular dark brown blotches appearing from eye level to the urostyle region. In life, ventral surfaces of males are golden yellow on throat and chest, and white to yellow on abdomen. Ventral surfaces of females are predominantly white, except for light yellow on chin. The dark brown lateral band has a diffuse lower edge ventrolaterally. Dorsal surface of thigh is cream, with a longitudinal dark brown band extending dorsally from vent to knee. Tail musculature of tadpoles is robust, bifurcating dorsally over the body and reaching about two-thirds of the body length. Advertisement calls consist predominantly of continuous pairs of notes, but other note arrangements are also emitted. Notes have ascending frequency modulation and average peak frequency ranging between 5.3-5.9 kHz. First and second notes of the same note pair are similar in amplitude, duration and frequency spectrum. Successive note pairs are split by approximately regular silent intervals (0.30-0.49 s). The species lays its eggs inside rolled or folded dead leaves on the leaf litter. Egg capsules and jelly nests are opaque.


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Animais , Brasil , Feminino , Larva/anatomia & histologia , Masculino
11.
Zootaxa ; 3889(3): 355-87, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25544274

RESUMO

We describe a new species of Allobates from the south of eastern Amazonia, Brazil. This species inhabits fluvial springs and the banks of small streams in terra-firme forests along the Tapajós River basin. Average snout-to-vent length is 17.78 mm (range 16.09-19.59 mm) among males and 19.50 mm (range 17.97-20.84 mm) among females. Surface of dorsum is marked by a distinct dark color pattern, with three convex areas, triangle and diamond-shaped. The species has a diffuse pale dorsolateral line (absent in some specimens), while the oblique lateral bar is defined. Dark-brown transversal stripes are present on femoral and tibial dorsal surfaces, which align with each other in live specimens when at rest. Tadpoles have short papillae on anterior (8-10 papillae on each side) and posterior labium (>30 papillae). Posterior labium is projected to the front, hiding posterior tooth rows. Eggs are deposited in nests on rolled or cranked dead leaves on the forest floor. Egg membranes and jelly-nests are transparent. Advertisement calls are mainly characterized by the continuous emission of single notes that might shift sporadically to note-pairs, emitted during short periods. Notes are split by regular silent intervals, with peak frequency ranging between 4273-4867 Hz. 


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/genética , Anuros/crescimento & desenvolvimento , Tamanho Corporal , Brasil , Feminino , Masculino , Tamanho do Órgão
12.
Zootaxa ; 3746: 401-21, 2013 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25113485

RESUMO

We describe the advertisement calls and color in life of Allobates sumtuosus (Morales 2002) based on specimens recorded and collected at its type locality in Reserva Biológica do Rio Trombetas, Brazilian Amazonia. We also improve the species diagnosis by adding information on states of characters frequently used in current Allobates taxonomy. Finally, we analyze genetic distances and the evolutionary relationships between typical A. sumtuosus and other Allobates species distributed in Brazil and along the Guiana Shield region using a fragment of the 16S rDNA mitochondrial gene. Based on this integrative analysis, we propose the synonym of Allobates spumaponens Kok & Ernst 2007 with A. sumtuosus and provide an updated geographic distribution of the species.


Assuntos
Anuros/classificação , Anuros/fisiologia , Vocalização Animal , Distribuição Animal , Animais , Anuros/anatomia & histologia , Anuros/genética , Brasil , DNA Mitocondrial/genética , Dados de Sequência Molecular , Filogenia , Pigmentação , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Zootaxa ; 3609: 251-73, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24699589

RESUMO

We describe Allobates grillisimilis from the northwestern region of the Rio Madeira-Rio Tapajós interfluve, state of Am-azonas, Brazil. The new taxon is characterized by its small snout-to-vent length (12.8-16.0 mm, the smallest among known Allobates), by the color pattern of adults (surfaces of throat, chest and abdomen unpigmented), by morphological traits of larvae (a single row of very elongate papillae on posterior labium), and by its distinctive advertisement call, formed by trills of short pulses emitted in a variable number. We also provide notes on reproductive behavior of the new species.


Assuntos
Anuros , Animais , Anuros/anatomia & histologia , Anuros/classificação , Anuros/fisiologia , Brasil , Feminino , Estágios do Ciclo de Vida , Masculino , Vocalização Animal
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