A new species of Osteocephalus (Anura: Hylidae) from Guyana.

A new member of the genus Osteocephalus is described from the Pakaraima mountains of western Guyana. This species is the smallest known member of the genus and is probably closely related to O. subtilis. Both share a small size (less than 40 mm snout-vent length), large and bulgy eyes directed somewhat rostrally, green bones, smooth and brownish dorsal skin, relatively short and truncate snout, small tympanum, subgular and laterally expanded vocal sac, poorly developed subarticular and supernumerary tubercles, a supra-anal glandular ridge, and cream-white venter and subocular region. The new species can be distinguished from O. subtilis by the Buff iris (vs black), smaller overall size (32.7 vs 35.8-38.8 mm snout-vent length), relatively larger toe disks, and less developed foot webbing. The cranium of the new species is well ossified, relatively reduced in width between the orbits, without an exposed frontoparietal fontanelle and with the anterior arm of the squamosal extending to about half the distance to the maxillary. The vocal sac is subgularly poorly developed and possess lateral extensions to the area behind the jaw angles. Well developed supraocular and suprasquamosal cartilages give support to the enlarged eyes of this species.     

The thermal physiology of two sympatric treefrogs Hyla cinerea and Hyla chrysoscelis (Anura; Hylidae)

Metabolic rates, temperature acclimation, lipid deposition and temperature tolerance were investigated in two species of hylid treefrogs, the green treefrog (Hyla cinerea) and the coastal plain (Cope's) gray treefrog (Hyla chrysoscelis). The rate of oxygen consumption at rest differed between the two species only at 30 degrees C; there was no difference in respiratory metabolism at lower ambient temperatures. Hyla cinerea generally completed metabolic acclimation earlier than H. chrysoscelis, particularly at high temperatures; both species appeared to be fully acclimated in 6 days or less. The gray treefrog is less tolerant of high ambient temperatures than the green treefrog; mean upper lethal temperature was 41.5 degrees C for Hyla chrysoscelis and 43.7 degrees C for H. cinerea. Metabolized energy was higher at high ambient temperatures (i.e. 29 degrees C) for H. chrysoscelis than H. cinerea, while the reverse was true at 19 degrees C. The coefficient of utilization (100 X metabolized energy/gross energy intake) did not vary significantly between species or within species over the ambient temperature range of 19-24 degrees C; H. chrysoscelis had a significantly higher efficiency at 29 degrees C. Lipid reserves were generally similar in the two species throughout the summer. Differences in behavior, seasonal variation in activity and timing of reproduction are all related to thermal physiology and may play a role in determining the distributional limits of the two species.     

Systematics of treefrogs of the Hypsiboas calcaratus and Hypsiboas fasciatus species complex (Anura,Hylidae) with the description of four new species

We review the systematics of the Hypsiboas calcaratus species complex, a group of widely distributed Amazonian hylid frogs. A comprehensive analysis of genetic, morphological, and bioacoustic datasets uncovered the existence of eleven candidate species, six of which are confirmed. Two of them correspond to Hypsiboas fasciatus and Hypsiboas calcaratus and the remaining four are new species that we describe here. Hypsiboas fasciatus sensu stricto has a geographic range restricted to the eastern Andean foothills of southern Ecuador while Hypsiboas calcaratus sensu stricto has a wide distribution in the Amazon basin. Hypsiboas almendarizae sp. n. occurs at elevations between 500 and 1950 m in central and northern Ecuador; the other new species (H. maculateralis sp. n., H. alfaroi sp. n., and H. tetete sp. n.) occur at elevations below 500 m in Amazonian Ecuador and Peru. The new species differ from H. calcaratus and H. fasciatus in morphology, advertisement calls, and mitochondrial and nuclear DNA sequences. Five candidate species from the Guianan region, Peru, and Bolivia are left as unconfirmed. Examination of the type material of Hyla steinbachi, from Bolivia, shows that it is not conspecific with H. fasciatus and thus is removed from its synonymy.     

A total evidence analysis of the phylogeny of hatchet-faced treefrogs (Anura: Hylidae: Sphaenorhynchus)

The Neotropical hylid genus Sphaenorhynchus includes 15 species of small, greenish treefrogs widespread in the Amazon and Orinoco basins, and in the Atlantic Forest of Brazil. Although some studies have addressed the phylogenetic relationships of the genus with other hylids using a few exemplar species, its internal relationships remain poorly understood. In order to test its monophyly and the relationships among its species, we performed a total evidence phylogenetic analysis of sequences of three mitochondrial and three nuclear genes, and 193 phenotypic characters from all species of Sphaenorhynchus. Our results support the monophyly of Sphaenorhynchus with molecular and phenotypic evidence, with S. pauloalvini as the earliest diverging taxon, followed by S. carneus, as the sister taxon of all remaining species of the genus. We recognize three species groups in Sphaenorhynchus (the S. lacteus, S. planicola and S. platycephalus groups), to facilitate its taxonomic study; only three species (S. carneus, S. pauloalvini and S. prasinus) remain unassigned to any group. Sequence data were not available for only two species (S. bromelicola and S. palustris) for which we scored phenotypic data; wildcard behaviour was detected only in S. bromelicola nested inside the S. platycephalus group. On the basis of the resulting phylogenetic hypothesis, we discuss the evolution of oviposition site and a number of phenotypic characters that could be associated with heterochronic events in the evolutionary history of this group.     

New species of Parapharyngodon (Nematoda: Pharyngodonidae) parasite of Osteocephalus taurinus (Anura: Hylidae) from Northern Brazilian Amazon Region

Systematic Parasitology - Parapharyngodon spp. are nematodes parasites of amphibian and reptiles worldwide distributed. Of 55 valid species, only 11 are known for the Neotropical realm, and six...     

Taxonomic revision and phylogenetic position of Osteocephalus festae (Anura, Hylidae) with description of its larva

Osteocephalus festae is an Amazonian species recently resurrected from a synonymy with Osteocephalus buckleyi. Because few specimens are known, its morphological variation, diagnostic characters, and distribution are poorly understood. Herein we determine its phylogenetic relationships and provide a complete taxonomic account based on recently collected specimens (adults and larvae) from nine localities in Ecuador and Peru. Osteocephalus festae is most similar to Osteocephalus verruciger from which it differs in having less tuberculate dorsal skin on males, smaller tympanum, and more tooth rows in the oral disk of larvae. A phylogeny based on mitochondrial DNA sequences, genes 12S and ND1, shows that Osteocephalus festae is closely related to Osteocephalus buckleyi, Osteocephalus mutabor and Osteocephalus verruciger. A clade consisting of Osteocephalus festae, Osteocephalus verruciger, and Osteocephalus buckleyi is characterized by stream dwelling tadpoles. Surprisingly, we found paraphyly among Ecuadorian populations of Osteocephalus buckleyi and Osteocephalus verruciger. The causes for paraphyly are unknown but in Osteocephalus buckleyi may result from the existence of cryptic species.     

Diversity and evolution of sexually dimorphic mental and lateral glands in Cophomantini treefrogs (Anura: Hylidae: Hylinae)

We describe the structure and histochemistry of mental and lateral glands in a representative array of 28 species of five genera of the Neotropical hylid frog tribe Cophomantini. Structural diversity was coded in 15 characters that were optimized on the most recent phylogenetic hypothesis. Mental and lateral glands occur in 17 species and 10 species, respectively, whereas nine species have both. Each glandular concentration may have two types of sexually dimorphic skin glands (SDSGs), specialized mucous and specialized serous glands, which occur independently or may co‐occur. Distinctive characteristics related to these glands are shape, aspect of the secretion, disposition, and distribution. The occurrences of mental and lateral glands, and the characters derived from macroscopic and microscopic examinations, have an intricate taxonomic distribution, with differing levels of homoplasy. The function of SDSGs in Cophomantini is currently unknown. However, based on structural and histochemical similarities to SDSGs from other species of amphibians where experimental evidence exists, we infer they might be involved in the secretion of chemical signals during courtship behaviour. The distribution pattern of these glands, along with the existence of different signals (i.e. acoustic, visual, tactile), suggests the presence of multimodal signalling for some species of the tribe. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 114 , 12–34.     

Pattern recognition and call preferences in treefrogs (Anura: Hylidae): a quantitative analysis using a no-choice paradigm

Studies of mate attraction have traditionally employed one of two experimental methods: choice tests in which female preferences from among two or more signals are tabulated, or single-stimulus tests in which the female response to one signal is quantified. Choice tests have long been preferred for examining mate attraction in anurans. Inspired by Wagner's (1998, Animal Behaviour,55, 1029-1042) discussion of the strengths and weaknesses of the two experimental approaches, we used a single-stimulus design to examine mate attraction in two sibling species of treefrogs (Hyla versicolor and H. chrysoscelis). We quantified female responses based upon the relative time required to approach signals varying in pulse rate, pulse rise time and pulse number. The data were used to generate response functions providing a quantitative measure of female attraction to the stimuli. Comparisons with data from choice experiments reveal broad similarities, as well as properties of female responses that had not been detected with choice tests. The results are discussed with regard to female selectivity for call parameters that are likely to mediate sexual selection and homospecific pairing.     

Evolutionary history of spiny‐tailed lizards (Agamidae: Uromastyx) from the Saharo‐Arabian region

The subfamily Uromastycinae within the Agamidae is comprised of 18 species: three within the genus Saara and 15 within Uromastyx. Uromastyx is distributed in the desert areas of North Africa and across the Arabian Peninsula towards Iran. The systematics of this genus has been previously revised, although incomplete taxonomic sampling or weakly supported topologies resulted in inconclusive relationships. Biogeographic assessments of Uromastycinae mostly agree on the direction of dispersal from Asia to Africa, although the timeframe of the cladogenesis events has never been fully explored. In this study, we analysed 129 Uromastyx specimens from across the entire distribution range of the genus. We included all but one of the recognized taxa of the genus and sequenced them for three mitochondrial and three nuclear markers. This enabled us to obtain a comprehensive multilocus time‐calibrated phylogeny of the genus, using the concatenated data and species trees. We also applied coalescent‐based species delimitation methods, phylogenetic network analyses and model‐testing approaches to biogeographic inferences. Our results revealed Uromastyx as a monophyletic genus comprised of five groups and 14 independently evolving lineages, corresponding to the 14 currently recognized species sampled. The onset of Uromastyx diversification is estimated to have occurred in south‐west Asia during the Middle Miocene with a later radiation in North Africa. During its Saharo‐Arabian colonization, Uromastyx underwent multiple vicariance and dispersal events, hypothesized to be derived from tectonic movements and habitat fragmentation due to the active continental separation of Arabia from Africa and the expansion and contraction of arid areas in the region.     

High Species Richness of Scinax Treefrogs (Hylidae) in a Threatened Amazonian Landscape Revealed by an Integrative Approach

Rising habitat loss is one of the main drivers of the global amphibian decline. Nevertheless, knowledge of amphibian diversity needed for effective habitat protection is still highly inadequate in remote tropical regions, the greater part of the Amazonia. In this study we integrated molecular, morphological and bioacoustic evidence to evaluate the species richness of the treefrogs genus Scinax over a 1000 km transect across rainforest of the Purus-Madeira interfluve, and along the east bank of the upper Madeira river, Brazilian Amazonia. Analysis revealed that 82% of the regional species richness of Scinax is still undescribed; two nominal species, seven confirmed candidate species, two unconfirmed candidate species, and one deep conspecific lineage were detected in the study area. DNA barcoding based analysis of the 16s rRNA gene indicates possible existence of three discrete species groups within the genus Scinax, in addition to the already-known S. rostratus species Group. Quantifying and characterizing the number of undescribed Scinax taxa on a regional scale, we provide a framework for future taxonomic study in Amazonia. These findings indicate that the level to which Amazonian anura species richness has been underestimated is far greater than expected. Consequently, special attention should be paid both to taxonomic studies and protection of the still-neglected Amazonian Scinax treefrogs.     

Systematics of the Osteocephalus buckleyi species complex (Anura,Hylidae) from Ecuador and Peru

We present a new phylogeny, based on DNA sequences of mitochondrial and nuclear genes, for frogs of the genus Osteocephalus with emphasis in the Osteocephalus buckleyi species complex. Genetic, morphologic, and advertisement call data are combined to define species boundaries and describe new species. The phylogeny shows strong support for: (1) a basal position of Osteocephalus taurinus + Osteocephalus oophagus, (2) a clade containing phytotelmata breeding species, and (3) a clade that corresponds to the Osteocephalus buckleyi species complex. Our results document a large proportion of hidden diversity within a set of populations that were previously treated as a single, widely distributed species, Osteocephalus buckleyi. Individuals assignable to Osteocephalus buckleyi formed a paraphyletic group relative to Osteocephalus verruciger and Osteocephalus cabrerai and contained four species, one of which is Osteocephalus buckleyi sensu stricto and three are new. Two of the new species are shared between Ecuador and Peru (Osteocephalus vilmae sp. n. and Osteocephalus cannatellai sp. n.) and one is distributed in the Amazon region of southern Peru (Osteocephalus germani sp. n.) We discuss the difficulties of using morphological characters to define species boundaries and propose a hypothesis to explain them.     

Systematics of Andean gladiator frogs of the Hypsiboas pulchellus species group (Anura,Hylidae)

Köhler, J., Koscinski, D., Padial, J. M., Chaparro, J. C., Handford, P., Lougheed, S. C. & De la Riva, I. (2010). Systematics of Andean gladiator frogs of the Hypsiboas pulchellus species group (Anura, Hylidae). —Zoologica Scripta, 39, 572–590. We revisit the taxonomic status of Andean species and populations of frogs of the Hypsiboas pulchellus group using multiple lines of evidence potentially indicative of evolutionary lineage divergence in anurans: differences in qualitative morphological or bioacoustic character states, no overlap in quantitative characters of advertisement calls, and monophyly of gene genealogies. We found qualitative and quantitative morphological characters to be extremely variable among species and populations of the group and thus of very limited use in assessing lineage divergence. In contrast, phylogenetic analyses based on 16S rRNA and cytochrome b sequences resolved highly supported clades that are in concordance with bioacoustic differences. The results support the specific distinctness of most nominal species recognized in the group, including the Bolivian Hypsiboas balzani and Hypsiboas callipleura, two species that were considered to be synonymous, and revealed the presence of an undescribed species from southern Peru, which is here described as Hypsiboas gladiator sp. n. In contrast, Hypsiboas andinus and Hypsiboas riojanus were mutually paraphyletic, and showed no differences in morphology and acoustic characters. Consequently, we regard the former as a junior synonym of the latter. However, we discovered that populations of H. riojanus from central Bolivia exhibit some degree of genetic differentiation and advertisement call differences with respect to Argentine populations, but sampling of these Bolivian populations is too sparse to draw taxonomic conclusions. Our phylogenetic results support the hypothesis that ancestral lineages of the Andean H. pulchellus group experienced successive splitting events along a latitudinal gradient from north to south.     

Characterization of microsatellite markers for snouted treefrogs in the Scinax perpusillus species group (Anura, Hylidae)

We characterized eight microsatellite loci for snouted treefrogs in the Scinax perpusillus species group, a group of hylid frogs endemic to the Atlantic Coastal Forest of Brazil, and tested their utility in mainland and island species of the complex. All eight loci were polymorphic in one population of S. perpusillus; four of the loci showed excess homozygosity and three of those deviated from Hardy–Weinberg expectations, possibly due to null alleles, inbreeding, or population structure in sampled individuals. Six loci amplified and were polymorphic in S. arduous, S. argyreornatus, and S. faivovichi, but only one in S. alcatraz. These markers will be useful for quantifying effects of habitat fragmentation on population genetic diversity and connectivity in coastal and island populations of this threatened species group.     

The phylogeny of the Casque‐headed Treefrogs (Hylidae: Hylinae: Lophyohylini)

The South American and West Indian Casque‐headed Treefrogs (Hylidae: Hylinae: Lophyohylini) include 85 species. These are notably diverse in morphology (e.g. disparate levels of cranial hyperossification) and life history (e.g. different reproductive modes, chemical defences), have a wide distribution, and occupy habitats from the tropical rainforests to semiarid scrubland. In this paper, we present a phylogenetic analysis of this hylid tribe based on sequence fragments of up to five mitochondrial (12S, 16S, ND1, COI, Cytb) and six nuclear genes (POMC, RAG‐1, RHOD, SIAH, TNS3, TYR). We included most of its species (> 96%), in addition to a number of new species. Our results indicate: (i) the paraphyly of Trachycephalus with respect to Aparasphenodon venezolanus; (ii) the nonmonophyly of Aparasphenodon, with Argenteohyla siemersi, Corythomantis galeata and Nyctimantis rugiceps nested within it, and Ap. venezolanus nested within Trachycephalus; (iii) the polyphyly of Corythomantis; (iv) the nonmonophyly of the recognized species groups of Phyllodytes; and (v) a pervasive low support for the deep relationships among the major clades of Lophyohylini, including C. greeningi and the monotypic genera Itapotihyla and Phytotriades. To remedy the nonmonophyly of Aparasphenodon, Corythomantis, and Trachycephalus, we redefined Nyctimantis to include Aparasphenodon (with the exception of Ap. venezolanus, which we transferred to Trachycephalus), Argenteohyla, and C. galeata. Additionally, our results indicate the need for taxonomic work in the following clades: (i) Trachycephalus dibernardoi and Tr. imitatrix; (ii) Tr. atlas, Tr. mambaiensis and Tr. nigromaculatus; and (iii) Phyllodytes. On the basis of our phylogenetic results, we analyzed the evolution of skull hyperossification and reproductive biology, with emphasis on the multiple independent origins of phytotelm breeding, in the context of Anura. We also analyzed the inter‐related aspects of chemical defences, venom delivery, phragmotic behaviour, co‐ossification, and prevention of evaporative water loss.     

Isolation of dinucleotide microsatellite loci from red‐backed salamander (Plethodon cinereus)

We isolated 13 variable dinucleotide microsatellites from red‐backed salamanders (Plethodon cinereus). After generating fragments using degenerate oligonucleotide primer‐polymerase chain reaction (DOP‐PCR), AC repeats were captured using biotinylated probes and streptavidin‐coated magnetic particles. Captured fragments were cloned into plasmids, screened for microsatellites with a simple PCR reaction, and select plasmids then sequenced. PCR primers were designed and optimized for robust amplification, and nine primers have been further optimized for multiplex reactions with fluorescent primers. These nine loci are variable with an average of 6.11 alleles per locus and an average heterozygosity of 0.61.     

Genetic diversity and evolutionary history of the Tyrrhenian treefrog Hyla sarda (Anura: Hylidae): adding pieces to the puzzle of Corsica–Sardinia biota

The Corsica–Sardinia archipelago is a hotspot of Mediterranean biodiversity. Although tempo and mode of arrival of species to this archipelago and phylogenetic relationships with continental species have been investigated in many taxa, very little is known about the current genetic structure and evolutionary history subsequent to arrival. In the present study, we investigated genetic variation within and among populations of the Tyrrhenian treefrog Hyla sarda, a species endemic to the Corsica–Sardinia microplate and the surrounding islands, by means of allozyme electrophoresis. Low genetic divergence (mean D_nei = 0.01) and no appreciable differences in the levels and distribution of genetic variability (H_E: 0.06–0.09) were observed among all but one populations (Elba). Historical demographic and isolation‐by‐distance analyses indicated that this diffused genetic homogeneity could be the result of recent demographic expansion. Along with paleoenvironmental data, such expansion could have occurred during the last glacial phase, when wide and persistent land bridges connected the main islands and a widening of lowland areas occurred. This scenario is unprecedented among Corsica–Sardinia species. Together with the lack of concordance even among the few previously studied species, this suggests either that species had largely independent responses to paleoenvironmental changes, or that most of the history of assembly of the Corsica–Sardinia biota is yet to be written. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 159–167.     

Systematics and evolution of the Pan‐Alcidae (Aves,Charadriiformes)

Puffins, auks and their allies in the wing‐propelled diving seabird clade Pan‐Alcidae (Charadriiformes) have been proposed to be key pelagic indicators of faunal shifts in Northern Hemisphere oceans. However, most previous phylogenetic analyses of the clade have focused only on the 23 extant alcid species. Here we undertake a combined phylogenetic analysis of all previously published molecular sequence data (～ 12 kb) and morphological data (n = 353 characters) with dense species level sampling that also includes 28 extinct taxa. We present a new estimate of the patterns of diversification in the clade based on divergence time estimates that include a previously vetted set of twelve fossil calibrations. The resultant time trees are also used in the evaluation of previously hypothesized paleoclimatic drivers of pan‐alcid evolution. Our divergence dating results estimate the split of Alcidae from its sister taxon Stercorariidae during the late Eocene (～ 35 Ma), an evolutionary hypothesis for clade origination that agrees with the fossil record and that does not require the inference of extensive ghost lineages. The extant dovekie Alle alle is identified as the sole extant member of a clade including four extinct Miocene species. Furthermore, whereas an Uria + Alle clade has been previously recovered from molecular analyses, the extinct diversity of closely related Miocepphus species yields morphological support for this clade. Our results suggest that extant alcid diversity is a function of Miocene diversification and differential extinction at the Pliocene–Pleistocene boundary. The relative timing of the Middle Miocene climatic optimum and the Pliocene–Pleistocene climatic transition and major diversification and extinction events in Pan‐Alcidae, respectively, are consistent with a potential link between major paleoclimatic events and pan‐alcid cladogenesis.