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

[EN] 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 confrmed. 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. © M.A. Caminer, S.R. Ron.[ES] Revisamos la sistemática del complejo de especies Hypsiboas calcaratus, un grupo de ranas hílidas de amplia distribución en la Amazonía. Un análisis exhaustivo de datos genéticos, morfológicos y bioacústicos revelaron la existencia de once especies candidatas, de las cuales seis son confirmadas. Dos de ellas corresponden a Hypsiboas fasciatus e Hypsiboas calcaratus y las cuatro restantes son especies nuevas que describimos aquí. Hypsiboas fasciatus sensu stricto tiene un rango geográfico restringido a las estribaciones orientales de los Andes del sur del Ecuador, mientras que Hypsiboas calcaratus sensu stricto tiene una distribución amplia en la cuenca amazónica. Hypsiboas almendarizae sp. n. se encuentra a alturas entre los 500 y 1950 m en el centro y el norte del Ecuador, mientras que las otras nuevas especies (H. maculateralis sp. n., H. alfaroi sp. n. y H. tetete sp. n.) se encuentran a elevaciones bajo 500 m en la Amazonía de Ecuador y Perú. Las nuevas especies difieren de H. calcaratus e H. fasciatus en morfología, cantos de anuncio y secuencias de ADN mitocondrial y nuclear. Cinco especies candidatas de la región de las Guayanas, Perú y Bolivia quedan como no confirmadas. La examinación del material tipo de Hyla steinbachi indica que no es conespecífica con H. fasciatus y por lo tanto se remueve de su sinonimia.Peer Reviewe

Mating Patterns and Post-Mating Isolation in Three Cryptic Species of the Engystomops Petersi Species Complex

Determining the extent of reproductive isolation in cryptic species with dynamic geographic ranges can yield important insights into the processes that generate and maintain genetic divergence in the absence of severe geographic barriers. We studied mating patterns, propensity to hybridize in nature and subsequent fertilization rates, as well as survival and development of hybrid F1 offspring for three nominal species of the Engystomops petersi species complex in Yasuní National Park, Ecuador. We found at least two species in four out of six locations sampled, and 14.3% of the wild pairs genotyped were mixed-species (heterospecific) crosses. We also found reduced fertilization rates in hybrid crosses between E. petersi females and E. “magnus” males, and between E. “magnus” females and E. “selva” males but not in the reciprocal crosses, suggesting asymmetric reproductive isolation for these species. Larval development times decreased in F1 hybrid crosses compared to same species (conspecific) crosses, but we did not find significant reduction in larval survival or early metamorph survival. Our results show evidence of post-mating isolation for at least two hybrid crosses of the cryptic species we studied. The general decrease in fertilization rates in heterospecific crosses suggests that sexual selection and reinforcement might have not only contributed to the pattern of call variation and behavioral isolation we see between species today, but they may also contribute to further signal divergence and behavioral evolution, especially in locations where hybridization is common and fertilization success is diminished

Mating Patterns and Post-Mating Isolation in Three Cryptic Species of the Engystomops Petersi Species Complex

Determining the extent of reproductive isolation in cryptic species with dynamic geographic ranges can yield important insights into the processes that generate and maintain genetic divergence in the absence of severe geographic barriers. We studied mating patterns, propensity to hybridize in nature and subsequent fertilization rates, as well as survival and development of hybrid F1 offspring for three nominal species of the Engystomops petersi species complex in Yasuní National Park, Ecuador. We found at least two species in four out of six locations sampled, and 14.3% of the wild pairs genotyped were mixed-species (heterospecific) crosses. We also found reduced fertilization rates in hybrid crosses between E. petersi females and E. “magnus” males, and between E. “magnus” females and E. “selva” males but not in the reciprocal crosses, suggesting asymmetric reproductive isolation for these species. Larval development times decreased in F1 hybrid crosses compared to same species (conspecific) crosses, but we did not find significant reduction in larval survival or early metamorph survival. Our results show evidence of post-mating isolation for at least two hybrid crosses of the cryptic species we studied. The general decrease in fertilization rates in heterospecific crosses suggests that sexual selection and reinforcement might have not only contributed to the pattern of call variation and behavioral isolation we see between species today, but they may also contribute to further signal divergence and behavioral evolution, especially in locations where hybridization is common and fertilization success is diminished

Ecological and genetic divergence between two lineages of Middle American túngara frogs Physalaemus (= Engystomops) pustulosus

<p>Abstract</p> <p>Background</p> <p>Uncovering how populations of a species differ genetically and ecologically is important for understanding evolutionary processes. Here we combine population genetic methods (microsatellites) with phylogenetic information (mtDNA) to define genetic population clusters of the wide-spread Neotropical túngara frog (<it>Physalaemus pustulosus</it>). We measure gene flow and migration within and between population clusters and compare genetic diversity between population clusters. By applying ecological niche modeling we determine whether the two most divergent genetic groups of the túngara frog (1) inhabit different habitats, and (2) are separated geographically by unsuitable habitat across a gap in the distribution.</p> <p>Results</p> <p>Most population structure is captured by dividing all sample localities into two allopatric genetic lineages. The Northern genetic lineage (NW Costa Rica) is genetically homogenous while the Southern lineage (SW Costa Rica and Panama) is sub-divided into three population clusters by both microsatellite and mtDNA analyses. Gene flow is higher within the Northern lineage than within the Southern lineage, perhaps due to increased landscape heterogeneity in the South. Niche modeling reveals differences in suitable habitat between the Northern and Southern lineages: the Northern lineage inhabits dry/pine-oak forests, while the Southern lineage is confined to tropical moist forests. Both lineages seem to have had little movement across the distribution gap, which persisted during the last glacial maximum. The lack of movement was more pronounced for the Southern lineage than for the Northern lineage.</p> <p>Conclusions</p> <p>This study confirms the finding of previous studies that túngara frogs diverged into two allopatric genetic lineages north and south of the gap in the distribution in central Costa Rica several million years ago. The allopatric distribution is attributed to unsuitable habitat and probably other unknown ecological factors present across the distribution gap. Niche conservatism possibly contributes to preventing movements across the gap and gene flow between both groups. Genetic and ecological data indicate that there is the potential for ecological divergence in allopatry between lineages. In this context we discuss whether the Northern and Southern lineages should be recognized as separate species, and we conclude that further studies of pre- and post-zygotic isolation are needed for a final assessment. Identified population clusters should motivate future behavioral and ecological research regarding within-species biodiversity and speciation mechanisms.</p

Advertisement calls and DNA sequences reveal a new species of Scinax (Anura: Hylidae) on the Pacific lowlands of Ecuador

Scinax is a speciose genus of Neotropical hylid frogs. We describe a new species from western Ecuador (elevations between 0 and 1207 m) using morphology, vocalizations, and DNA sequences. We also present a new phylogeny for Scinax based on mitochondrial DNA genes 12S rRNA, Cytochrome Oxidase sub-unit I, Cytochrome B, 16S rRNA, NADH dehydrogenase subunit 1, and adjacent tRNAs. The new species, Scinax tsachila sp. nov. was previously confused with S. quinquefasciatus, a morphologically similar sympatric species. They differ by having markedly different advisement calls, distinct skin texture in the dorsum, and different bone coloration. The new species is sister to S. elaeochroa, a species that differs in advertisement call and color pattern. We provide an updated species account for Scinax quinquefasciatus and a redescription of its holotype

Nueva especie de rana bromelícola del género Pristimantis (Amphibia: Craugastoridae), meseta de la Cordillera del Cóndor, Ecuador

We describe a small frog of the genus Pristimantis inhabiting bromeliads (snout-vent length 20.3‑23.3 mm in females, 16.1‑17.4 mm in males), from a remote sandstone plateau of the Cordillera del Condor, in southeastern Ecuador, with an altitudinal range of 2,045‑2,860 m. A phylogeny based on sequences of DNA (mitochondrial and nuclear genes) supports inclusion in the P. orestes group and suggests an undescribed Pristimantis from the southern slope of eastern Ecuador as the closest taxon. The new species differs from its congeners in Ecuador by having predominantly black dorsal and ventral coloration; comprehensive and robust palmar surface with stubby fingers; presence of a deep and wide groove from the anterior base of finger I to the rear base of the palmar tubercle; subarticular divided tubers, enlarged supernumerary small granules and tubercles. All individuals were found in terrestrial bromeliads. The calls are short, frequency modulated, comprising of a note 5‑15 ms in duration. Insects represented 80% of the diet of the new species.We describe a small frog of the genus Pristimantis inhabiting bromeliads (snout-vent length 20.3‑23.3 mm in females, 16.1‑17.4 mm in males), from a remote sandstone plateau of the Cordillera del Condor, in southeastern Ecuador, with an altitudinal range of 2,045‑2,860 m. A phylogeny based on sequences of DNA (mitochondrial and nuclear genes) supports inclusion in the P. orestes group and suggests an undescribed Pristimantis from the southern slope of eastern Ecuador as the closest taxon. The new species differs from its congeners in Ecuador by having predominantly black dorsal and ventral coloration; comprehensive and robust palmar surface with stubby fingers; presence of a deep and wide groove from the anterior base of finger I to the rear base of the palmar tubercle; subarticular divided tubers, enlarged supernumerary small granules and tubercles. All individuals were found in terrestrial bromeliads. The calls are short, frequency modulated, comprising of a note 5‑15 ms in duration. Insects represented 80% of the diet of the new species

Dos nuevas especies del grupo Pristimantis boulengeri (Anura: Strabomantidae) de la cuenca alta del río Napo, Ecuador

Through the combination of morphological and phylogenetic evidence, we describe two species of Pristimantis from the upper basin of the Napo River. Both species have well-defined dorsolateral folds, a conical tubercle on the eyelid, a papilla on the tip of the snout, weakly expanded discs, and small size (female SVL < 28.2 mm). Pristimantis omarrhynchus sp. nov. differs from its sister species, Pristimantis miltongallardoi sp. nov., by the absence of iridophores on the belly, subacuminate snout in dorsal view, and narrow digits. Our phylogeny and morphological evidence, are conclusive in assigning them to the Pristimantis boulengeri species group, closely related to P. boulengeri, P. cryptopictus, P. dorspictus, and P. brevifrons. The new species are the first reported for the P. boulengeri group in Ecuador and the Amazon basin. We also comment on the correct identity of GenBank sequences previously assigned to P. thymelensis and P. myersi.A través de la combinación de evidencia morfológica y filogenética describimos dos especies de Pristimantis de la cuenca alta del río Napo. Las dos especies presentan pliegues dorsolaterales bien definidos, un tubérculo cónico en el párpado, una papila en la punta del hocico, discos poco dilatados y tamaño pequeño (hembras LRC < 28,2 mm). Pristimantis omarrhynchus sp. nov. se diferencia de su especie hermana, Pristimantis miltongallardoi sp. nov., por la ausencia de iridóforos en el vientre, hocico subacuminado en vista dorsal y dígitos estrechos. Nuestra filogenia, en combinación con la evidencia morfológica, son concluyentes para asignarlas al grupo de especies Pristimantis boulengeri y cercanamente relacionadas a P. boulengeri, P. cryptopictus, P. dorspictus y P. brevifrons. Las nuevas especies son las primeras reportadas para el grupo P. boulengeri en el Ecuador y la cuenca amazónica. También comentamos la identidad correcta de secuencias GenBank previamente asignadas a P. thymelensis y P. myersi.Asociación Herpetológica Argentin

A new species of spiny-backed tree frog, genus Osteocephalus (Anura, Hylidae), from the Yanachaga Chemillén National Park in central Peru

We describe a new species of Osteocephalus Fitzinger, 1843 using morphological traits of adult frogs and its larvae, as well as molecular evidence. The new species occurs in the premontane forest of the Cordillera del Yanachaga in the Andes of central Peru, at elevations between 1000 and 1150 m a.s.l. It belongs to the Osteocephalus mimeticus species group and is the sister species of O. mimeticus. It is most similar to three species with predominantly dark irises, tuberculate dorsal skin, and brown dorsal coloration: O. festae Peracca, 1904, O. mimeticus Melin, 1941, and O. verruciger Werner, 1901. Of these three species, the most similar is O. mimeticus. However, the new species can be easily distinguished from O. mimeticus by having a cream or creamy-tan venter with a well-defined pattern of brown chocolate blotches and flecks (venter cream, tan, or brown without marks in O. mimeticus). The tadpoles of O. vasquezi sp. nov. are strikingly different from the tadpoles of O. mimeticus by having a larger oral disk with nine lower labial tooth rows (only six in O. mimeticus). Tadpoles of the new species and those of O. festae are unique among Osteocephalus by belonging to the suctorial ecomorphological guild as shown by their large oral disks. Our time tree suggest that the new species diverged from its sister species at the beginning of the Pleistocene, ~2.5 million years ago

Otra nueva especie de rana Pristimantis (Anura: Terrarana) de las estribaciones occidentales del Volcán Pichincha, Ecuador

We describe a new species of terrestrial frog Pristimantis from the western slopes of the Ecuadorian Andes, in the province of Pichincha, Ecuador. The species is a member of the P. devillei species-group and is characterized by having cranial crests with high frontoparietals, concealed tympanum, glandular dorsolateral folds and flanks, and subconical tubercles on the upper eyelid, ulnar region and heel.Describimos una nueva especie de rana terrestre Pristimantis de las estribaciones occidentales de los Andes de Ecuador, en la provincia de Pichincha, Ecuador. La especie forma parte del grupo de especies P. devillei y se caracteriza por presentar cresta craneal elevada frontoparietalmente, tímpano oculto, pliegues dorsolaterales, flancos glandulares, y tubérculos subcónicos en el párpado, región ulnar y talón

Una especie nueva de rana del género Chiasmocleis (Microhylidae: Gastrophryninae) de la Cordillera del Cóndor, Ecuador

We describe a new species of frog of the genus Chiasmocleis from the montane forests of southeastern Ecuador, at the western slopes of Cordillera del Cóndor, between 1,224‑1,630 m of elevation. Based on new sequences of mitochondrial and nuclear DNA we present phylogenetic relationships of the new species and its congeners. The phylogeny shows a close relationship to C. antenori, C. carvalhoi, C. magnova and C. tridactyla. The new species is part of a clade of species that were previously assigned to the genus Syncope. This clade has a sister relationship to a clade that contains all remaining species of Chiasmocleis. The new species differs from its congeners by its reddish-brown to dark-brown (sepia) dorsum with minute yellowish-white spots. Chiasmocleis parkeri sp. nov. is similar to Chiasmocleis antenori in lacking digit I of both hands and feet but Chiasmocleis parkeri differs in coloration, arrangement and size of pale spots, and the absence of a pale line in the canthal region. We describe the calls, which are characterized by having non-pulsed notes, and we provide ecological data from the type locality and adjacent areas