Species limits within the widespread Amazonian treefrog Dendropsophus parviceps with descriptions of two new species (Anura, Hylidae)

Three new species of torrent treefrogs (Anura, Hylidae) of the Hyloscirtusbogotensis group from the eastern Andean slopes and the biogeographic history of the genus

The Hyloscirtusbogotensis group contains 17 species of treefrogs from the tropical Andes and Central America. A taxonomic review of the Amazonian clades of this group is presented based on DNA sequences of nuclear and mitochondrial DNA and a preliminary phylogenomic analysis of ultraconserved elements, as well as morphological, bioacoustic, and environmental characters. Additionally, the role of the Andes in the diversification of the genus Hyloscirtus is explored by reconstructing their ancestral basin (Amazon, Pacific, Caribbean). Our integrative analysis indicates the existence of eight undescribed candidate species within the group. Three of those species are described, previously masked within H.albopunctulatus, H.phyllognathus, and H.torrenticola. A lectotype is also designated for Hylaalbopunctulata. The new evidence suggests that neither Hyloscirtusphyllognathus nor H.torrenticola occur in Ecuador. The new species, H.elbakyanae sp. nov., H.dispersus sp. nov., and Hyloscirtusmaycu sp. nov. differ from other members of the group in bioacoustics and external morphology. The most useful diagnostic characters among species were advertisement calls. In contrast, skin coloration is highly variable intraspecifically and, as a result, of low diagnostic value. High variation in color is partly a result of phenotypic plasticity. Our biogeographic reconstructions indicate that the Andean barrier influenced the diversification of Hyloscirtus. Since the early Oligocene, there have been only four colonization events across de Andes, between the Pacific and Amazon basins. Two of those events occurred more than 14 Mya, when most of the tropical Andes were below 3000 m. Species in the highland H.larinopygion group are younger, suggesting recent diversification as high montane forests and paramo habitats emerged.

Phylogenetics, biogeography, and life history evolution in the broadly distributed treefrog genus Dendropsophus (Anura: Hylidae: Hylinae)

Dendropsophusis one of the most species-rich genera of hylid treefrogs. Recent studies integrating Sanger-generated mitochondrial and nuclear loci with phenomic characters (SP) have advanced understanding of this clade, but questions about its internal relationships and biogeographic history persist. To address these questions, we used anchored hybrid enrichment (AHE) to combine 432 nuclear loci for 78 taxa (72 % of species) with published data. Quantitatively, the impact of the AHE data was modest, with compositional differences in only three recognized clades and more than 80 % of the clades in the AHE + SP analyses also supported in the SP-only analyses. Nevertheless, the impact of AHE was crucial for resolving and increasing support for multiple nodes. We transferred one species of the formerD. ruschiigroup to theD. decipiensgroup and redefined theD. leucophyllatusgroup to avoid paraphyly. We estimated divergence times to reconstruct the clade's biogeographic history. We also examined evolution of oviposition sites and assessed its effect on lineage accumulation. Dendropsophuslikely originated ∼ 57 mya, predating the Andean uplift, with some taxa showing dispersal patterns less constrained by ecological changes than previously thought.

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.

Subtle environmental variation affects phenotypic differentiation of shallow divergent treefrog lineages in Amazonia

Amazonia harbours a vast biotic and ecological diversity, enabling investigation of the effects of microevolutionary processes and environmental variation on species diversification. Integrative approaches combining phenotypic and genetic variation can improve our knowledge on diversification processes in megadiverse regions. Here, we investigate the influence of environmental and geographic variation on the genetic and morphological differentiation in the Amazonian Boana calcarata-fasciata (Anura: Hylidae) species complex. We analysed the variation of one mtDNA gene from individuals of different forest environments, and assessed their phylogenetic relationships and species limits to define the lineages to perform a phenotypic-environmental approach. We collected morphological data (head shape and size) using 3D models and investigated the phylogenetic signal, evolutionary model and influence of environmental variables on morphology. We verified associations between environmental and geographical distances with morphological and genetic variation using distance-based redundancy analyses and Mantel tests. We found an even higher cryptic diversity than already recognized within the species complex. Body size and head shape varied among specimens, but did not present phylogenetic signal, diverging under a selective evolutionary model. Our results show that diverse factors have influenced morphological and genetic variation, but environmental conditions such as vegetation cover, precipitation and climate change velocity influenced morphological diversification. Possible population-level mechanisms such as parallel morphological evolution or plastic responses to similar environments could account for such patterns in these typical Amazonian treefrogs.

A new species of Dendropsophus (Anura, Hylidae) from southwestern Amazonia with a green bilobate vocal sac

Recent studies have shown that species diversity of the South American frog genus Dendropsophus is significantly underestimated, especially in Amazonia. Herein, through integrative taxonomy a new species of Dendropsophus from the east bank of the upper Madeira River, Brazil is described. Based on molecular phylogenetic and morphological analyses, the new species is referred to the D. microcephalus species group, where it is differentiated from its congeners mainly by having a green bilobate vocal sac and an advertisement call comprising 1-4 monophasic notes emitted with a dominant frequency of 8,979-9,606 Hz. Based on intensive sampling conducted in the study area over the last ten years, the new species is restricted to the east bank of the upper Madeira River, although its geographic range is expected to include Bolivian forests close to the type locality.

Systematics of the Boana semilineata species group (Anura: Hylidae), with a description of two new species from Amazonian Ecuador

The combination of genetic and phenotypic characters for species delimitation has allowed the discovery of many undescribed species of Neotropical amphibians. In this study, we used DNA sequences (genes 12S, 16S, ND1 and COI) and morphologic, bioacoustic and environmental characters of the Boana semilineata group to evaluate their phylogenetic relationships and assess their species limits. In addition, we included DNA sequences of several species of Boana to explore cryptic diversity in other groups. We found three Confirmed Candidate Species (CCS) within the B. semilineata group. Holotype examination of Hyla appendiculata shows that it is a valid species that corresponds to one of the CCS, which is here transferred to Boana. We describe the two remaining CCS. Our phylogeny highlights a number of secondary but meaningful observations that deserve further investigation: (1) populations of B. pellucens from northern Ecuador are more closely related to B. rufitela from Panama than to other Ecuadorian populations of B. pellucens; (2) we report, for the first time, the phylogenetic relationships of B. rubracyla showing that it is closely related to B. rufitela and B. pellucens; and (3) B. cinerascens and B. punctata form two species complexes consisting of several unnamed highly divergent lineages. Each of these lineages likely represents an undescribed species.

Calls of Boanalatistriata (Caramaschi & Cruz, 2004) (Amphibia, Anura, Hylidae), an endemic tree frog from the State of Minas Gerais, Brazil

Bioacoustical data are useful for studying amphibians, especially their conservation, taxonomy, and evolution, among others. Of the 12 species of the Boanapolytaenia clade, only B.buriti and B.latistriata have no published information about their advertisement calls. We recorded four males of B.latistriata in its type locality at Parque Nacional do Itatiaia, south-eastern Brazil. We used a Roland R26 digital recorder with a Sennheiser ME-67 microphone and analysed the recordings using the Raven Pro 1.5 software. We recorded two different types of calls (call A and call B). Both were composed of one pulsed note and presented a slightly ascending-descending frequency modulation. Call A was more frequent, having durations between 0.042 and 0.093 s with the dominant frequency ranging from 3375.0 to 3937.5 Hz, and was composed of 11 to 21 pulses separated by intervals that were not fully silent. Call B had durations between 0.711 and 1.610 s, with dominant frequency from 3281.2 to 3750.0 Hz, and was composed of 11 to 29 pulses separated by fully silent intervals. Among the B.polytaenia clade, the calls of B.latistriata are more similar to those of B.bandeirantes, B.beckeri, B.polytaenia, and B.aff.beckeri. The calls of B.latistriata differ from these species in its lower dominant frequency. Boanalatistriata present a short, single-note call with a lower pulse period (call A) and a long call with higher pulse period (call B), which differ from the other species of the clade. The coefficients of variation for the various bioacoustical attributes were calculated within- and between-males and these have been discussed. We also report a fight event between two males of B.latistriata. This is the first report of a fight in members of the B.polytaenia clade.