Browsing by Author "Ron Melo, Santiago Rafael"
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A new species of direct-developing frog of the genus Pristimantis (Anura: Terrarana: Craugastoridae) from Cordillera del Cóndor, Ecuador, with comments on threats to the anuran fauna of the region(2017) Ron Melo, Santiago Rafael; Ron Melo, Santiago RafaelA new frog in the genus Pristimantis is described from a cloud forest on the western flanks of the Cordillera del Cóndor and eastern Andean slopes in the province of Zamora Chinchipe, southeastern of Ecuador. We inferred its phylogenetic position using DNA sequences of mitochondrial and nuclear genes. The new species is strongly supported as part of a clade that includes P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. chalceus, P. minutulus, P. luteolateralis, P. parvillus, P. ockendeni, P. unistrigatus, and P. walkeri. It can be distinguished from all other species from Cordillera del Cóndor and congeneric species by the unique combination of the following characters: (1) iris light blue with black reticulations; (2) skin of dorsum finely shagreen with scattered pustular tubercles and absence of dorsal folds; (3) tympanic membrane and tympanic annulus visible; (4) snout rounded in dorsal and lateral view; (5) upper eyelid bearing two or three enlarged subconical tubercles; (6) cranial crest absent; (7) males lacking vocal sac and slits; and (8) venter uniformly bright red, light red, salmon or orange. The new species is most closely related to P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. ockendeni and P. unistrigatus. We consider the new species to be Endangered following IUCN criteria because it has been severely affected by large scale open-pit mining in some localities. Currently, the amphibian fauna of the Cordillera del Cóndor and nearby protected areas are threatened by large–scale copper and gold mining projects with devastating effects on ~20 species, including several undescribed ones.Item Open Access Abundancia relativa de las especies de Aligatóridos presentes en el sistema hidrográfico del Río Yasuní y del Río Lagartococha en la Amazonía Ecuatoriana(PUCE - Quito, 2011) Arroba Benítez, Francisco; Ron Melo, Santiago RafaelSe estudió la biología poblacional de los aligatóridos del Parque Nacional Yasuní y la Reserva de Producción Faunística Cuyabeno en las épocas lluviosa y seca entre abril del 2007 y febrero del 2008. Se utilizó la técnica de conteos nocturnos estandarizados para determinar la abundancia relativa de caimanes presentes en las áreas de estudio, se estudió la composición poblacional por especies y tamaños. Se exploró la correlación de factores abióticos en los estimados de abundancia relativa así como la dependencia entre la abundancia relativa y la cercanía a centros poblados en el río Yasuní. Se determinó la preferencia de microhábitat por tamaño de las especies estudiadas.Item Open Access Advertisement calls and DNA sequences reveal a new species of Scinax (Anura: Hylidae) on the Pacific lowlands of Ecuador(2018-09) Ron Melo, Santiago Rafael; Ron Melo, Santiago RafaelScinax 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.Item Open Access Amphibians and reptiles of Wildsumaco Wildlife Sanctuary, Napo Province, Ecuador(2021-05) Ron Melo, Santiago Rafael; Ron Melo, Santiago Rafael y Torres Carvajal, Lenin OmarWe conducted a long-term inventory of the herpetofauna of Wildsumaco Wildlife Sanctuary in the eastern part of the Napo Province in Ecuador. This private preserve is about 500 ha in size and is located on the southern slopes of Volcán Sumaco. The preserve contains primary forest, secondary forest, and pasture habitats. Based mostly on nocturnal transect sampling we documented 39 species of amphibians including one species of salamander, two species of caecilians, and 36 species of frogs. Rain frogs (Pristimantis Jiminez de la Espada, 1871) were diverse with 14 species documented. A diverse species assemblage of 45 reptile species was also documented on the preserve. Six amphibian species found were listed by the IUCN Red List. At least three species exhibited substantial geographic range extensions and seven species showed elevational range extensions. We discovered several undescribed species including one salamander, three frogs, one lizard, and one snake.Item Open Access Ancient tepui summits harbor young rather than old lineages of endemic frogs.(2012) Ron Melo, Santiago Rafael; Salerno, Patricia E.The flattop mountains (tepuis) of South America are ancient remnants of the Precambrian Guiana Shield plateau. The tepui summits, isolated by their surrounding cliffs that can be up to 1000 m tall, are thought of as “islands in the sky,” harboring relict flora and fauna that underwent vicariant speciation due to plateau fragmentation. High endemicity atop tepui summits support the idea of an ancient “Lost World” biota. However, recent work suggests that dispersal between lowlands and summits has occurred long after tepui formation indicating that tepui summits may not be as isolated from the lowlands as researchers have long suggested. Neither view of the origin of the tepui biota (i.e., ancient vicariance vs. recent dispersal) has strong empirical support owing to a lack of studies. We test diversification hypotheses of the Guiana Shield highlands by estimating divergence times of an endemic group of treefrogs, Tepuihyla. We find that diversification of this group does not support an ancient origin for this taxon; instead, divergence times among the highland species are 2–5 Ma. Our data indicate that most highland speciation occurred during the Pliocene. Thus, this unparalleled landscape known as “The Lost World” is inhabited, in part, not by Early Tertiary relicts but neoendemics.Item Metadata only The birth of aposematism: high phenotypic divergence and low genetic diversity in a young clade of poison frogs(2017-04) Ron Melo, Santiago Rafael; Ron, Santiago R.Rapid radiation coupled with low genetic divergence often hinders species delimitation and phylogeny estimation even if putative species are phenotypically distinct. Some aposematic species, such as poison frogs (Dendrobatidae), have high levels of intraspecific color polymorphism, which can lead to overestimation of species when phenotypic divergence primarily guides species delimitation. We explored this possibility in the youngest origin of aposematism (3–7 MYA) in poison frogs, Epipedobates, by comparing genetic divergence with color and acoustic divergence. We found low genetic divergence (2.6% in the 16S gene) despite substantial differences in color and acoustic signals. While chemical defense is inferred to have evolved in the ancestor of Epipedobates, aposematic coloration evolved at least twice or was lost once in Epipedobates, suggesting that it is evolutionarily labile. We inferred at least one event of introgression between two cryptically colored species with adjacent ranges (E. boulengeri and E. machalilla). We also find evidence for peripheral isolation resulting in phenotypic divergence and potential speciation of the aposematic E. tricolor from the non-aposematic E. machalilla. However, we were unable to estimate a well-supported species tree or delimit species using multispecies coalescent models. We attribute this failure to factors associated with recent speciation including mitochondrial introgression, incomplete lineage sorting, and too few informative molecular characters. We suggest that species delimitation within young aposematic lineages such as Epipedobates will require genome-level molecular studies. We caution against relying solely on DNA barcoding for species delimitation or identification and highlight the value of phenotypic divergence and natural history in delimiting species.Item Open Access A bizarre new species of Lynchius (Amphibia, Anura, Strabomantidae) from the Andes of Ecuador and first report of Lynchius parkeri in Ecuador(2019) Ron Melo, Santiago Rafael; Ron Melo, Santiago RafaelWe describe a new species of Lynchius from the eastern montane forest of southern Ecuador. We also report the occurrence of L. parkeri in Ecuador, on paramos of Yacuri National Park, near the border with Peru. We used morphological and genetic evidence for the description of the new species and the new report of L. parkeri. Phylogenetic analyses were carried out using both maximum likelihood and Bayesian inference on DNA sequences for mitochondrial and nuclear genes. The phylogeny shows that L. simmonsi is sister to a clade composed of the remaining species of Lynchius and that the new species is sister to L. flavomaculatus. The new species has a prominent and heavily ossified head with noticeably spiculate cranial exostosis that easily distinguishes it from all its congeners. The dorsal region and limbs present several reduced subconical and rounded tubercles and pronounced dermal ridges on the dorsum. We also describe the osteology of the new species based on x-rays of the holotype. Only six species of Lynchius, two known to occur in Ecuador (L. flavomaculatus and L. simmonsi). The description of L. megacephalus sp. n. and new record of L. parkeri double the number of known Lynchius in Ecuador and suggest that the diversity of Ecuadorian and Peruvian Lynchius is still underestimated.Item Open Access Changes in Population Size and Survival in Atelopus spumarius (Anura: Bufonidae) are not Correlated with Chytrid Prevalence.(2014) Ron Melo, Santiago Rafael; Tarvin, RebeccaAproximadamente un tercio de las especies de anfibios experimentan declives poblacionales. Entre los grupos más afectados están las ranas Arlequín (Bufonidae: Atelopus), casi todas se encuentran en peligro de extinción. Monitoreamos el tamaño poblacional y la supervivencia de una de las últimas poblaciones ecuatorianas de Atelopus spumarius con un muestreo de marca-recaptura entre Febrero 2009 y Diciembre 2010. Debido a que Batrachochytrium dendrobatidis (Bd) había sido previamente registrado en el sitio, quisimos determinar su efecto en el tamaño poblacional y supervivencia. También analizamos el efecto de tala selectiva, la cual ocurrió a lo largo del transecto en Abril 2010. Diagnosticamos la presencia de Bd en cada individuo capturado o recapturado usando PCR de punto final. Las 679 muestras de Bd (provenientes de 356 individuos) fueron negativas, sugiriendo que Bd no influenció el tamaño poblacional y la supervivencia. El tamaño poblacional aumentó durante los nueve primeros meses del estudio (julio 2009–abril 2010) de un estimado de 47 a 92 individuos pero luego disminuyó en noviembre de 2010 a 48 individuos. La probabilidad de supervivencia fue 0.13 más baja en los meses posteriores a la tala selectiva que en los meses previos; emigración también disminuyó por 0.37 en los últimos meses. Parejas en amplexus fueron encontradas entre abril y diciembre, sugiriendo un período reproductivo largo, o incluso de duración anual. Aunque la mayoría de declives de Atelopus han sido atribuidos a infecciones de Bd, presentamos un caso en el que Bd ha sido detectado en el área, pero los cambios en el tamaño de la población no pueden ser atribuidos a quitridiomicosis. Análisis de supervivencia y del índice de la condición corporal en machos sugiere que el declive al final del estudio fue resultado de la destrucción del hábitat.Item Open Access Comportamiento social e historia natural de Hyloxalus yasuni e Hyloxalus sauli (Anura: Dendrobatidae) en el Parque Nacional Yasuní, Amazonía Ecuatoriana(PUCE - Quito, 2013) Paucar Guerra, Diego Andrés; Ron Melo, Santiago RafaelEn las últimas décadas, los dendrobátidos tóxicos y aposemáticos han sido objeto de múltiples estudios de comportamiento, ecología e historia natural lo cual ha contribuido al entendimiento de su biología y evolución. Sin embargo, esta información es aún inexistente para la gran mayoría de dendrobátidos crípticos, como lo son los miembros del género Hyloxalus. Se estudió el comportamiento social e historia natural de Hyloxalus yasuni e Hyloxalus sauli en el Parque Nacional Yasuní durante nueve meses abarcando la estación seca y lluviosa. Ambas especies habitan sintópicamente en quebradas pedregosas dentro del bosque. Hyloxalus yasuni está asociado a aguas corrientes e H. sauli a cavidades en el suelo. Machos y hembras de ambas defienden territorios pequeños a largo plazo, existiendo agresión intra e interespecífica. Los machos poseen un canto de anuncio y uno de agresión. Ambos sexos de H. yasuni emiten un tercer tipo de vocalización emitido en sincronía con ataques durante los encuentros agresivos. En H. yasuni las hembras son más agresivas, mientras que en los machos la combinación de señales visuales y acústicas parece minimizar las agresiones físicas entre ellos. El tamaño de los territorios de H. yasuni varía entre tipos de terreno (rocoso vs. plano), pero no entre sexos ni entre estaciones. La defensa de recursos no reproductivos parece ser el determinante para la territorialidad en ambos sexos y explicaría las agresiones intersexuales. En H. sauli existe unión de pareja donde el macho y la hembra defienden conjuntamente un único territorio donde parece primar la defensa de recursos no reproductivos, pero no se descarta la custodia de pareja.Item Open Access Cryptic diversity and biogeography of South American salamanders(PUCE - Quito, 2016) Hervas Sotomayor, Francisca; Ron Melo, Santiago RafaelTropical regions harbor a majority of Earth’s biodiversity. In most taxonomic groups there is a gradient of increasing diversity from polar to tropical latitudes. In a few groups, however, the gradient is partly inverted and species richness peaks in temperate regions. One of those groups are salamanders, a group with higher diversity in North and Middle America than in tropical South America. This inverse gradient could result from a time for diversification effect because they arrived more recently to South America. However, an additional contributing factor could be that salamander diversity is underestimated in South America. In this study we used mitochondrial and nuclear DNA sequences to obtain a more comprehensive phylogeny of South American salamanders, to estimate their time of colonization of this continent and assess their species diversity. Using published and new genetic data, we generated a time-calibrated phylogeny and reconstructed ancestral bioregions and altitudes to infer the colonization history of Bolitoglossa in South America. The phylogenetic analyses recognized 19 candidate species, of which 13 are confirmed candidate species. This represents an increase of at least 38% in the species content of South American salamanders demonstrating that species richness is severely underestimated. Our results show that the ancestor of Bolitoglossa first colonized middle altitudes of the Andes, between the Oligocene and the Miocene. Therefore, all extant species descend from an Andean ancestor, which subsequently colonized higher and lower elevations. Our results suggest that salamander history has been closely linked to the Andean uplift and agrees with previous studies showing that most of the South American biodiversity diversified prior to the Quaternary. Our results show that the Andes have been a species pump for lowland regions. This highlights the importance of the protection of montane regions to maintain the processes that promote species diversification of this group of organisms. We show that formally described species with wide geographical distributions are in fact species complexes on which each species has small geographic ranges. Therefore, the extinction probability of South American salamanders it is likely to be underestimated under the IUCN’s Red List.Item Restricted 
Descripción y relaciones filogenéticas de dos nuevas especies de Pristimantis crestadas (Anura: Terrarrana: Craugastoridae) de los Andes Norte de Ecuador(PUCE - Quito, 2014) Yánez Muñoz, Mario Humberto; Ron Melo, Santiago RafaelA través de un enfoque integrador, combinamos el uso de secuencias de ADN y características morfológicas para describir dos nuevas especies de Pristimantis de los Andes de Ecuador e inferir sus relaciones filogenéticas. La primera especie se distingue de sus congéneres por su distintiva cresta craneal con bordes frontoparietales fuertemente elevados en forma de “U”, tubérculo calcar en el talón, tubérculos cónicos en el párpado y en el codo, y hocico moderadamente largo y, redondo con pequeña papila rostral en la punta. La segunda, es la única especie de Pristimantis con crestas craneales que encierran los bordes y la parte anterior de los frontoparietales, tubérculos cónicos sobre los ojos, talón y codo, dedos de la mano III y IV crenulados y líneas irregulares amarillas conspicuas en los flancos. Nuestro análisis es congruente con filogenias publicadas previamente al mostrar un fuerte soporte para un clado integrado por especies caracterizadas por tener crestas craneales. Este clado incluye a miembros de los grupos de especies P. devillei. La filogenia muestra que el grupo es parafilético por lo que reorganizamos su taxonomía y proponemos el nombre Cristamantis para el clado de especies con crestas craneales.Item Metadata only Description and phylogenetic relationships of a new species of treefrog of the Osteocephalus buckleyi species group (Anura: Hylidae)(2020-02) Ron Melo, Santiago Rafael; Ron Melo, Santiago RafaelThe Osteocephalus buckleyi species group is widely distributed in primary and secondary forests of the Amazon Basin and Guiana Region. Based on integrative analysis, including morphological and genetic data, we estimate the phylogenetic relationships and species boundaries among populations of the Osteocephalus buckleyi group from the Ecuadorian Amazon, focusing on the O. verruciger-O. cannatellai species complex. Our results uncovered the existence of one confirmed candidate species from Sangay National Park and one unconfirmed candidate species. Here, we describe the new species which is morphologically and ecologically distinct from other Osteocephalus species. The new species is unusual because it shows quite distinct morphology, but low genetic distances compared to its closest relatives.Item Open Access Description and phylogenetic relationships of a new species of treefrog of the Osteocephalus buckleyi species group (Anura: Hylidae)(PUCE - Quito, 2019) Chasiluisa Pincay, Valeria Dennisse; Ron Melo, Santiago RafaelThe Osteocephalus buckleyi species group is widely distributed in primary and secondary forests of South America. Based on integrative analysis, including morphological and genetic data, we estimate the phylogenetic relationships and species boundaries among populations of the Osteocephalus buckleyi group from the Ecuadorian Amazon, focusing on the O. verruciger-O. cannatellai species complex. Our results uncovered the existence of one confirmed candidate species from Sangay National Park and one unconfirmed candidate species. Here, we describe the new species which is morphologically and ecologically distinct from other Osteocephalus species. The new species is unusual because it shows quite distinct morphology, but low genetic distances compared to its closest relatives.Item Metadata only Description and phylogenetic relationships of a new trans-Andean species of Elachistocleis Parker 1927 (Amphibia, Anura, Microhylidae)(2020-05) Ron Melo, Santiago Rafael; Ron Melo, Santiago RafaelElachistocleis is a Neotropical genus of microhylid frogs with 18 species, most of which occur east of the Andes in South America. Here, we present a new phylogeny of Gastrophryninae and describe and name a new species of Elachistocleis from southern Ecuador—the first to be found west of the Andes and also the first from Ecuador. Our phylogeny is based on DNA sequences of the mitochondrial genes 12S rRNA, 16S rRNA, COI, and the nuclear genes BDNF, cmyc2, H3A, 28S, SIA1, and Tyr. Elachistocleis araios sp. n., is the sister species of all other Elachistocleis. The finding of this taxon highlights the probability of the existence of more Elachistocleis species west of the Andes.Item Open Access Description of a new species of glassfrog from “El Quimi” Reserve in the Cordillera del Condor (Anura, Centrolenidae, Nymphargus)(PUCE - Quito, 2023) Masache Sarango, Mylena Victoria; Ron Melo, Santiago RafaelWith 34 species, the genus Nymphargus is characterized by the absence of humeral spines among other characters. To differentiate between the species of this genus can be somewhat complex since you have to look at the details to identify cryptic species. In this study we present an updated phylogeny of the Nymphargus genus showing the new species and also the phylogenetic position of N. buenaventura for the first time. The new species is characterized by not having spots on the dorsum, shagreen skin and white esophagus and stomach. The new species is closely related to a couple of undescribed species.Item Open Access Discovering Hidden Diversity of Characins (Teleostei: Characiformes) in Ecuador’s Yasuní National Park(2015-08-14) Ron Melo, Santiago Rafael; Ron Melo, Santiago RafaelManagement and conservation of biodiversity requires adequate species inventories. The Yasuní National Park is one of the most diverse regions on Earth and recent studies of terrestrial vertebrates, based on genetic evidence, have shown high levels of cryptic and undescribed diversity. Few genetic studies have been carried out in freshwater fishes from western Amazonia. Thus, in contrast with terrestrial vertebrates, their content of cryptic diversity remains unknown. In this study, we carried out genetic and morphological analyses on characin fishes at Yasuní National Park, in eastern Ecuador. Our goal was to identify cryptic diversity among one of the most speciose fish families in the Amazon region. This is the first time that genetic evidence has been used to assess the species content of the Napo Basin, one of the richest regions in vertebrate diversity. Results: Phylogenetic analyses of partial mitochondrial 16S ribosomal RNA gene (∼600 pb) DNA sequences from 232 specimens of the family Characidae and its closest groups revealed eight candidate new species among 33 species sampled, representing a 24% increase in species number. Analyses of external morphology allowed us to confirm the species status of six of the candidate species. Conclusions: Our results show high levels of cryptic diversity in Amazonian characins. If this group is representative of other Amazonian fish, our results would imply that the species richness of the Amazonian ichthyofauna is highly underestimated. Molecular methods are a necessary tool to obtain more realistic inventories of Neotropical freshwater fishes.Item Metadata only Disease reservoirs threaten the recently rediscovered Podocarpus Stubfoot Toad (Atelopus podocarpus)(2020) Merino Viteri, Andrés Ricardo; Ron Melo, Santiago Rafael; Merino Viteri, Andrés RicardoThe Andes have experienced an unprecedented wave of amphibian declines and extinctions that are linked to a combination of habitat reduction and the spread of the fungal pathogen, Batrachochytrium dendrobatidis (Bd). In the present study, a range of high-altitude habitats in Southern Ecuador were surveyed for the presence of Bd. With a particular focus on Yacuri National Park, infection data are presented from across the resident amphibian community. This community contains a once putatively extinct species which was rediscovered in 2016, the Podocarpus Stubfoot Toad (Atelopus podocarpus). Across species, local Bd prevalence was 73% in tadpoles (n = 41 individuals from three species) and 14% in adults (n = 43 individuals from 14 species). Strikingly, 93% (14/15) of tested tadpoles of the recently described local endemic, Gastrotheca yacuri, were infected with a high pathogen load, suggesting that this species likely acts as a reservoir of infection in Yacuri. These findings show that the threat of disease for A. podocarpus still exists, and that this species requires urgent action to ensure its survival.Item Open Access Diversidad críptica y relaciones filogenéticas de la familia Characidae (Ostariophysi: Characiformes) en el Yasuní, Ecuador(PUCE - Quito, 2013) Escobar Camacho, Daniel; Ron Melo, Santiago RafaelCharacidae es una familia de peces neotropicales perteneciente al orden Characiformes. Esta familia ha sido analizada durante las últimas décadas en base a caracteres morfológicos y genéticos. Characidae se caracteriza por su gran riqueza de especies y por tener relaciones filogenéticas complejas y presumiblemente alta diversidad críptica. En este trabajo se realizó un análisis filogenético de especies de carácidos colectadas en el Parque Nacional Yasuní, provincia de Orellana, Ecuador, para identificar posibles linajes de especies nuevas y contribuir al entendimiento de sus relaciones filogenéticas. Se amplificó un fragmento (600 pb) del gen mitocondrial 16S. Las secuencias de ADN obtenidas junto con secuencias de Characidae provenientes del GenBank fueron analizadas bajo los criterios filogenéticos de Máxima Verosimilitud e Inferencia Bayesiana...Item Metadata only Diversification history of clown tree frogs in Neotropical rainforests (Anura, Hylidae, Dendropsophus leucophyllatus group)(2020-09) Ron Melo, Santiago Rafael; Ron Melo, Santiago RafaelGeneral consensus emphasizes that no single biological process can explain the patterns of species’ distributions and diversification in the Neotropics. Instead, the interplay of several processes across space and time must be taken into account. Here we investigated the phylogenetic relationships and biogeographic history of tree frogs in the Dendropsophus leucophyllatus species group (Amphibia: Hylidae), which is distributed across Amazonia and the Atlantic rainforests. Using Next Generation Sequencing (NGS) and double digest restriction-site associated DNA (ddRADseq), we inferred phylogenetic relationships, species limits, and temporal and geographic patterns of diversification relative to the history of these biomes. Our results indicate that the D. leucophyllatus species group includes at least 14 independent lineages, which are currently arranged into ten described species. Therefore, a significant portion of species in the group are still unnamed. Different processes were associated to the group diversification history. For instance, the Andes uplift likely caused allopatric speciation for Cis-Andean species, whereas it may also be responsible for changes in the Amazonian landscape triggering parapatric speciation by local adaptation to ecological factors. Meanwhile, Atlantic Forest ancestors unable to cross the dry diagonal biomes after rainforest’s retraction, evolved in isolation into different species. Diversification in the group began in the early Miocene, when connections between Atlantic Forest and the Andes (Pacific Dominion) by way of a south corridor were possible. The historical scenario in Amazonia, characterized by several speciation events and habitat heterogeneity, helped promoting diversification, resulting in the highest species diversity for the group. This marked species diversification did not happen in Atlantic Forest, where speciation is very recent (late Pliocene and Pleistocene), despite its remarkable climatic heterogeneity.Item Open Access Ecological and genetic divergence between two lineages of Middle American túngara frogs Physalaemus (=Engystomops) pustulosus(2010) Ron Melo, Santiago Rafael; Pröhl, Heike.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 (Physalaemus pustulosus). 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. 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. 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.