The phylogeny of Dendropsophini (Anura: Hylidae: Hylinae).

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.

Phylogenetic relationships of toads of the Rhinella granulosa group (Anura: Bufonidae): a molecular perspective with comments on hybridization and introgression.

The Rhinella granulosa group consists of 13 species of toads distributed throughout open areas of South America and Panama. In this paper we perform a phylogenetic analysis considering all but one species of the group, employing five nuclear and four mitochondrial genes, for up to 7910 bp per specimen. Separate phylogenetic analyses under direct optimization (DO) of nuclear and mitochondrial sequences recovered the R. granulosa group as monophyletic and revealed topological incongruence that can be explained mainly by multiple events of hybridization and introgression, both mitochondrial and nuclear. The DO combined analysis, after the exclusion of putatively introgressed or heterozygous genomes, resulted in a phylogenetic hypothesis for the R. granulosa group in which most of the species are recovered as monophyletic, but with interspecific relationships poorly supported. The optimization of morphological (adult and larval), chromosomal, and behavioural characters resulted in 12 putative phenotypic synapomorphies for this species group and some other synapomorphies for internal clades. Our results indicate the need for additional population genetic studies on R. dorbignyi and R. fernandezae to corroborate the taxonomic status of both taxa. Finally, we discuss biological and genetic characteristics of Bufonidae, as possible explanations for the common occurrence of hybridization and introgression observed in some lineages of this family.

Aposematism increases acoustic diversification and speciation in poison frogs.

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.

A new tuberculated Pristimantis (Anura, Terrarana, Strabomantidae) from the Venezuelan Andes, redescription of Pristimantis pleurostriatus, and variation within Pristimantis vanadisae.

A new tuberculated Pristimantis is described from the eastern versant of the Venezuelan Andes. The new species is found in cloud forest at around 1600 masl on the eastern side of the Cordillera de Mérida. It is distinguished from other similar tuberculated species by its round, ill-defined canthus rostralis, ill-defined canthal stripe, and absence of pale spots on the groin and posterior surface of thighs. Pristimantis pleurostriatus is a poorly known species found in cloud forest on the western slopes of the Venezuelan Andes. We redescribe the species based on topotypic specimens. Pristimantis vanadisae is a polychomatic species varying dramatically in pattern; four chromotypes are described. Molecular data are presented which distinguish among tuberculated and other species of Pristimantis in the Cordillera de Merida. Molecular data also support placement of Mucubatrachus and Paramophrynella in Pristimantis.

On the taxonomic validity of Pristimantis tepuiensis (Schlüter & Rödder, 2007) and P. stegolepis (Schlüter & Rödder, 2007), with remarks on the type series of P. guaiquinimensis (Schlüter & Rödder, 2007).

The type series of Pristimantis guaiquinimensis (Schlüter & Rödder, 2007), P. tepuiensis (Schlüter & Rödder, 2007) and P. stegolepis (Schlüter & Rödder, 2007) have been thoroughly examined. We highlight a number of discrepancies in the original descriptions that do not support the recognition of P. stegolepis and P. tepuiensis as valid species. We demonstrate that P. stegolepis should be considered ajunior synonym of P. vilarsi (Melin, 1941), and that P. tepuiensis should be considered a junior synonym of P. guaiquinimensis. We also point out that the sex of the holotype and paratype of P. guaiquinimensis have been wrongly determined.

Discovery of an additional piece of the large gymnophthalmid puzzle: a new genus and species of stream spiny lizard (Squamata: Gymnophthalmidae: Cercosaurinae) from the western Guiana Shield in Venezuela.

Gymnophthalmids are a highly diverse group of Neotropical lizards and its species richness is still in process of discovery. The incorporation of molecular evidence and a noticeable increase in taxon and geographic sampling in systematic studies has led to the description of numerous new genera and species of gymnophthalmids (particularly in Cercosaurinae) in recent years. Herein we describe a new genus and species of cercosaurine lizard with crocodile-like morphology, from the Venezuelan Guiana Shield on the basis of molecular phylogenetic and morphological evidence. Kataphraktosaurus gen. nov. can be readily distinguished from all other genera of Cercosaurinae by a unique combination of morphological characters that includes heterogeneous dorsal scalation with enlarged and strongly keeled scales forming two paravertebral rows, ventral and subcaudal scales imbricated and strongly keeled, large and symmetrical cephalic scales, absence of postmental scale, palpebral disc translucent and divided, tail slightly compressed, all digits clawed, and only six femoral pores (three at each hindlimb) inserted in a clump of small scales. This genus is described as monotypic and only contains Kataphraktosaurus ungerhamiltoni sp. nov., which is known from one specimen and diagnosed by the same set of aforementioned characters. The secretive habits of this species and the remoteness of the locality may explain its singleton situation. Following the International Union for Conservation of Nature's criteria, we categorized the new species as Data Deficient.

The phylogenetic relationships of the charismatic poster frogs, Phyllomedusinae (Anura, Hylidae).

The leaf or monkey frogs of the hylid subfamily Phyllomedusinae are a unique group of charismatic anurans. We present a molecular phylogenetic analysis that includes 45 of the 60 species of phyllomedusines using up to 12 genes and intervening tRNAs. The aims were to gain a better understanding of the phylogenetic position of Phrynomedusa, test the monophyly and explore the relationships among several putative lineages (Hylomantis, the H. buckleyi Group, Phasmahyla, the four species groups of Phyllomedusa, and the species of Phyllomedusa that remain unassigned to any group), and to examine the implications of our phylogeny for the evolution of several characters in phyllomedusines. The analyses resulted in a well-supported phylogenetic hypothesis that provides a historical framework for a discussion of the evolution of characters associated with reproductive biology, gliding behaviour, the physiology of waterproofing, and bioactive peptides. Implications include an earlier origin for eggless capsules than for leaf-folding behaviour during amplexus, two independent origins of gliding, and an earlier origin of reduction in evaporative water loss than uricotelism, which is a result that originally was predicted on the basis of physiology alone. Furthermore, our results support the prediction that bioactive peptides from different peptide families are to be expected in all species of Phyllomedusinae. Hylomantis (as recently redefined) is shown to be paraphyletic and the synonymy of Agalychnis is revised to remedy this problem by including both Hylomantis and Pachymedusa. © The Willi Hennig Society 2009.

Geographic variation and taxonomy of red-tailed Gymnophthalmus (Squamata: Gymnophthalmidae) from Amazonian Savannas.

Gymnophthalmus represents a challenging group for systematics of microteiid lizards. Due to scarcity of exemplars and molecular data, the taxonomy of the genus has been unstable, and six of its eight species are considered part of a poorly-delimited complex of unisexual and bisexual species. Unnamed populations of red-tailed Gymnophthalmus from savanna enclaves in Amazon, similar to G. vanzoi but with differences in color pattern, have been noted in the literature. Here, we used molecular and morphological data to test the taxonomic status of the Central Amazonian red-tailed Gymnophthalmus (G. sp.). Our molecular analysis recovered a close relationship between G. vanzoi and G. sp. from Central Amazon, with minimal divergence. Samples were similar in scale counts but presented significant variation in color pattern and morphometry. Despite the geographic isolation, individuals of both populations cannot be fully differentiated based on morphology. Thus, our results suggest that G. vanzoi has a wider distribution, including the Central Amazonian red-tailed Gymnophthalmus and likely morphologically similar populations from other enclaves of Amazonian savannas, which may have been isolated recently. Based on our comparative analysis, we highlight some characters proved useful for differentiating Brazilian Gymnophthalmus and discuss some prospects for the taxonomy of the genus.

Real-time DNA barcoding in a rainforest using nanopore sequencing: opportunities for rapid biodiversity assessments and local capacity building.

Background: Advancements in portable scientific instruments provide promising avenues to expedite field work in order to understand the diverse array of organisms that inhabit our planet. Here, we tested the feasibility for in situ molecular analyses of endemic fauna using a portable laboratory fitting within a single backpack in one of the world's most imperiled biodiversity hotspots, the Ecuadorian Chocó rainforest. We used portable equipment, including the MinION nanopore sequencer (Oxford Nanopore Technologies) and the miniPCR (miniPCR), to perform DNA extraction, polymerase chain reaction amplification, and real-time DNA barcoding of reptile specimens in the field. Findings: We demonstrate that nanopore sequencing can be implemented in a remote tropical forest to quickly and accurately identify species using DNA barcoding, as we generated consensus sequences for species resolution with an accuracy of >99% in less than 24 hours after collecting specimens. The flexibility of our mobile laboratory further allowed us to generate sequence information at the Universidad Tecnológica Indoamérica in Quito for rare, endangered, and undescribed species. This includes the recently rediscovered Jambato toad, which was thought to be extinct for 28 years. Sequences generated on the MinION required as few as 30 reads to achieve high accuracy relative to Sanger sequencing, and with further multiplexing of samples, nanopore sequencing can become a cost-effective approach for rapid and portable DNA barcoding. Conclusions: Overall, we establish how mobile laboratories and nanopore sequencing can help to accelerate species identification in remote areas to aid in conservation efforts and be applied to research facilities in developing countries. This opens up possibilities for biodiversity studies by promoting local research capacity building, teaching nonspecialists and students about the environment, tackling wildlife crime, and promoting conservation via research-focused ecotourism.

Venezuelan geckos (Gekkonidae, Phyllodactylidae, Sphaerodactylidae) in the collection of the Universidad de Concepción in Chile, with description of the type series of Gonatodes ligiae and Gonatodes petersi (Sphaerodactylidae).

Herein we catalogue all geckos (Gekkonidae, Phyllodactylidae and Sphaerodactylidae) collected by Roberto Donoso-Barros in Venezuela between 1963 and 1964, deposited in the Universidad de Concepción in Chile. Donoso-Barros did not provide detailed descriptions of two species of Gonatodes named by him, despite both being valid species. We take the opportunity to do so and the type series of Gonatodes ligiae and G. petersi are described for the first time. We also present images in life of all species collected by Donoso-Barros in Venezuela.

Molecular and morphological data support recognition of a new genus of New World direct-developing frog (Anura: Terrarana) from an under-sampled region of South America.

We describe a new genus of New World direct-developing frog (Terrarana) from the northern Andes of Venezuela and adjacent Colombia. Tachiramantis gen. nov. includes three species formerly placed in the large genus Pristimantis. Molecular phylogenetic analysis of data from five nuclear and mitochondrial genes shows that Tachiramantis is not part of Pristimantis or any other named genus in its family (Craugastoridae or Strabomantidae). Morphological evidence further supports the distinctiveness of Tachiramantis, which has several aspects of skull morphology that are rare or absent in Pristimantis and synapomorphic for Tachiramantis, including frontoparietal-prootic fusion and degree of vomer development. The terminal phalanges, which narrow greatly before expanding at the tips, may represent an additional morphological synapomorphy. One species, T. prolixodiscus, also displays a fenestra between the posterior portions of the frontoparietals, a character state otherwise present in only 1 of 98 other sampled terraranan species. We use mapped ranges of most New World direct-developing frogs to show that Tachiramantis occurs in a geographic region that had been under-sampled in previous molecular studies of New World direct-developing frogs. Other under-sampled regions are identified in western Peru, Colombia, and northern Central America; these regions should provide fruitful target taxa for future phylogenetic studies.