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Ignacio De La Riva - One of the best experts on this subject based on the ideXlab platform.

  • systematics of oreobates and the Eleutherodactylus discoidalis species group amphibia anura based on two mitochondrial dna genes and external morphology
    Zoological Journal of the Linnean Society, 2008
    Co-Authors: Jose M Padial, Juan C Chaparro, Ignacio De La Riva
    Abstract:

    We present morphological and molecular (mitochondrial DNA, mtDNA) evidence supporting the validity and monophyly of the genus Oreobates. This genus also includes members of the former Eleutherodactylus discoidalis species group plus Eleutherodactylus heterodactylus. The presence of prominent conical subarticular tubercles and prominent supernumerary tubercles associated with the axis of fingers and toes, the presence of glandular axillary pads, and the absence of vocal sacs are proposed as morphological synapomorphies. Species of this taxon form a well-supported crown clade in a phylogeny including members of the genera Craugastor and Eleutherodactylus s.l. The sister taxon to Oreobates is the Eleutherodactylus martinicensis series; Oreobates does not appear to be closely related to the Eleutherodactylus binotatus series or to members of the Eleutherodactylus dolops and Eleutherodactylus nigrovittatus species groups. The taxonomic status of all species of Oreobates is reassessed. Hylodes philippi and Hylodes verrucosus are removed from the synonymy of Oreobates quixensis. We redescribe Oreobates cruralis on the basis of the holotype and new material from Bolivia and Peru, and restrict its distribution to the humid forests of the lowlands and adjacent foothills of the Andes, from southern Peru to central Bolivia. Oreobates granulosus is rediscovered, redescribed, and resurrected, on the basis of the examination of the holotype and additional material from Peru. Phylogenetic analyses of partial 16S mtDNA are used to test the independence of lineages (species). The 14 species of Oreobates are distributed from southern Ecuador to northern Argentina. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152, 737–773.

  • assessing the taxonomic status of tropical frogs through bioacoustics geographical variation in the advertisement calls in the Eleutherodactylus discoidalis species group anura
    Zoological Journal of the Linnean Society, 2008
    Co-Authors: Jose M Padial, Jorn Kohler, Arturo Munoz, Ignacio De La Riva
    Abstract:

    The taxonomic status of a very poorly known group of Andean frogs (the Eleutherodactylus discoidalis group) is assessed through acoustic and statistical analyses of differences in temporal parameters of advertisement calls, such as the number of pulses and the call duration, and also in a spectral parameter, dominant frequency. As these species are usually misidentified or ignored because of their taxonomic complexity in both ecological and biodiversity studies, we provide a bioacoustical diagnosis for each species in order to facilitate identification in the field. Differences in acoustic parameters support the specific status of Eleutherodactylus cruralis, E. discoidalis, Eleutherodactylus ibischi, and Eleutherodactylus madidi. The name E. cruralis is probably applied to three different species: the nominal form from Amazonian forests of the Andean slopes and adjacent lowlands, and two cryptic species restricted to inter-Andean dry valleys and cloud forests from central Bolivia. Moreover, the distribution of energy through the call and the aggregation of pulses seem to be useful meristic characters for detecting interspecific differences. Populations from each macrohabitat can be recognized by distinctive advertisement calls, usually corresponding to a recognized species. For the whole group, pulse rate is significantly correlated to latitude, which could indicate a speciation process along the Andes in relation to habitat changes and isolation. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152, 353–365.

  • systematics of the Eleutherodactylus fraudator species group anura brachycephalidae
    Herpetological Monographs, 2007
    Co-Authors: Jose M Padial, Jorn Kohler, Santiago Castroviejofisher, Enrique Domic, Ignacio De La Riva
    Abstract:

    Abstract Members of the Eleutherodactylus fraudator species group occur in Bolivia and Peru. This group has not been reviewed since its proposal and description. Its putative monophyly has not been...

  • a new species of the Eleutherodactylus discoidalis group anura brachycephalidae from cloud forests of peru
    Herpetologica, 2007
    Co-Authors: Jose M Padial, Juan C Chaparro, Ignacio De La Riva
    Abstract:

    We describe a new species of the Eleutherodactylus discoidalis group from cloud forests of the Apurimac and Kosnipata valleys, southern Peru. The new species differs from other species of the group mainly by having a coarsely shagreen dorsum, long and slender hind legs, very long feet, Finger I equal in length to Finger II and fingertips not expanded. The species also lacks supernumerary tubercles on the feet.

  • rediscovery redescription and advertisement call of Eleutherodactylus heterodactylus miranda ribeiro 1937 anura leptodactylidae and notes on other Eleutherodactylus
    Journal of Herpetology, 2005
    Co-Authors: Jose M Padial, Ignacio De La Riva
    Abstract:

    Abstract Eleutherodactylus heterodactylus was rediscovered in Cerrado montane forest of eastern Bolivia, 250–300 km airline from its type locality in Brazil, in similar habitat. The advertisement call is described for the first time. This species shares morphological features with species of the Eleutherodactylus binotatus and Eleutherodactylus discoidalis groups but is not assigned to either group pending further study. We confirm that Eleutherodactylus crepitans and Eleutherodactylus dundeei are valid species easily distinguishable from Eleutherodactylus fenestratus. Bolivian populations of the Andes previously assigned to E. dundeei correspond to an undescribed species allied to Eleutherodactylus peruvianus.

Jose M Padial - One of the best experts on this subject based on the ideXlab platform.

  • systematics of oreobates and the Eleutherodactylus discoidalis species group amphibia anura based on two mitochondrial dna genes and external morphology
    Zoological Journal of the Linnean Society, 2008
    Co-Authors: Jose M Padial, Juan C Chaparro, Ignacio De La Riva
    Abstract:

    We present morphological and molecular (mitochondrial DNA, mtDNA) evidence supporting the validity and monophyly of the genus Oreobates. This genus also includes members of the former Eleutherodactylus discoidalis species group plus Eleutherodactylus heterodactylus. The presence of prominent conical subarticular tubercles and prominent supernumerary tubercles associated with the axis of fingers and toes, the presence of glandular axillary pads, and the absence of vocal sacs are proposed as morphological synapomorphies. Species of this taxon form a well-supported crown clade in a phylogeny including members of the genera Craugastor and Eleutherodactylus s.l. The sister taxon to Oreobates is the Eleutherodactylus martinicensis series; Oreobates does not appear to be closely related to the Eleutherodactylus binotatus series or to members of the Eleutherodactylus dolops and Eleutherodactylus nigrovittatus species groups. The taxonomic status of all species of Oreobates is reassessed. Hylodes philippi and Hylodes verrucosus are removed from the synonymy of Oreobates quixensis. We redescribe Oreobates cruralis on the basis of the holotype and new material from Bolivia and Peru, and restrict its distribution to the humid forests of the lowlands and adjacent foothills of the Andes, from southern Peru to central Bolivia. Oreobates granulosus is rediscovered, redescribed, and resurrected, on the basis of the examination of the holotype and additional material from Peru. Phylogenetic analyses of partial 16S mtDNA are used to test the independence of lineages (species). The 14 species of Oreobates are distributed from southern Ecuador to northern Argentina. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152, 737–773.

  • assessing the taxonomic status of tropical frogs through bioacoustics geographical variation in the advertisement calls in the Eleutherodactylus discoidalis species group anura
    Zoological Journal of the Linnean Society, 2008
    Co-Authors: Jose M Padial, Jorn Kohler, Arturo Munoz, Ignacio De La Riva
    Abstract:

    The taxonomic status of a very poorly known group of Andean frogs (the Eleutherodactylus discoidalis group) is assessed through acoustic and statistical analyses of differences in temporal parameters of advertisement calls, such as the number of pulses and the call duration, and also in a spectral parameter, dominant frequency. As these species are usually misidentified or ignored because of their taxonomic complexity in both ecological and biodiversity studies, we provide a bioacoustical diagnosis for each species in order to facilitate identification in the field. Differences in acoustic parameters support the specific status of Eleutherodactylus cruralis, E. discoidalis, Eleutherodactylus ibischi, and Eleutherodactylus madidi. The name E. cruralis is probably applied to three different species: the nominal form from Amazonian forests of the Andean slopes and adjacent lowlands, and two cryptic species restricted to inter-Andean dry valleys and cloud forests from central Bolivia. Moreover, the distribution of energy through the call and the aggregation of pulses seem to be useful meristic characters for detecting interspecific differences. Populations from each macrohabitat can be recognized by distinctive advertisement calls, usually corresponding to a recognized species. For the whole group, pulse rate is significantly correlated to latitude, which could indicate a speciation process along the Andes in relation to habitat changes and isolation. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152, 353–365.

  • systematics of the Eleutherodactylus fraudator species group anura brachycephalidae
    Herpetological Monographs, 2007
    Co-Authors: Jose M Padial, Jorn Kohler, Santiago Castroviejofisher, Enrique Domic, Ignacio De La Riva
    Abstract:

    Abstract Members of the Eleutherodactylus fraudator species group occur in Bolivia and Peru. This group has not been reviewed since its proposal and description. Its putative monophyly has not been...

  • a new species of the Eleutherodactylus discoidalis group anura brachycephalidae from cloud forests of peru
    Herpetologica, 2007
    Co-Authors: Jose M Padial, Juan C Chaparro, Ignacio De La Riva
    Abstract:

    We describe a new species of the Eleutherodactylus discoidalis group from cloud forests of the Apurimac and Kosnipata valleys, southern Peru. The new species differs from other species of the group mainly by having a coarsely shagreen dorsum, long and slender hind legs, very long feet, Finger I equal in length to Finger II and fingertips not expanded. The species also lacks supernumerary tubercles on the feet.

  • rediscovery redescription and advertisement call of Eleutherodactylus heterodactylus miranda ribeiro 1937 anura leptodactylidae and notes on other Eleutherodactylus
    Journal of Herpetology, 2005
    Co-Authors: Jose M Padial, Ignacio De La Riva
    Abstract:

    Abstract Eleutherodactylus heterodactylus was rediscovered in Cerrado montane forest of eastern Bolivia, 250–300 km airline from its type locality in Brazil, in similar habitat. The advertisement call is described for the first time. This species shares morphological features with species of the Eleutherodactylus binotatus and Eleutherodactylus discoidalis groups but is not assigned to either group pending further study. We confirm that Eleutherodactylus crepitans and Eleutherodactylus dundeei are valid species easily distinguishable from Eleutherodactylus fenestratus. Bolivian populations of the Andes previously assigned to E. dundeei correspond to an undescribed species allied to Eleutherodactylus peruvianus.

Gerhard Schlosser - One of the best experts on this subject based on the ideXlab platform.

  • development of the retinotectal system in the direct developing frog Eleutherodactylus coqui in comparison with other anurans
    Frontiers in Zoology, 2008
    Co-Authors: Gerhard Schlosser
    Abstract:

    Frogs primitively have a biphasic life history with an aquatic larva (tadpole) and a usually terrestrial adult. However, direct developing frogs of the genus Eleutherodactylus have lost a free living larval stage. Many larval structures never form during development of Eleutherodactylus, while limbs, spinal cord, and an adult-like cranial musculoskeletal system develop precociously. Here, I compare growth and differentiation of the retina and tectum and development of early axon tracts in the brain between Eleutherodactylus coqui and the biphasically developing frogs Discoglossus pictus, Physalaemus pustulosus, and Xenopus laevis using morphometry, immunohistochemical detection of proliferating cell nuclear antigen (PCNA) and acetylated tubulin, biocytin tracing, and in situ hybridization for NeuroD. Findings of the present study indicate that retinotectal development was greatly altered during evolution of Eleutherodactlyus mostly due to acceleration of cell proliferation and growth in retina and tectum. However, differentiation of retina, tectum, and fiber tracts in the embryonic brain proceed along a conserved slower schedule and remain temporally coordinated with each other in E. coqui. These findings reveal a mosaic pattern of changes in the development of the central nervous system (CNS) during evolution of the direct developing genus Eleutherodactylus. Whereas differentiation events in directly interconnected parts of the CNS such as retina, tectum, and brain tracts remained coordinated presumably due to their interdependent development, they were dissociated from proliferation control and from differentiation events in other parts of the CNS such as the spinal cord. This suggests that mosaic evolutionary changes reflect the modular character of CNS development.

  • Frontiers in Zoology BioMed Central
    2008
    Co-Authors: Gerhard Schlosser
    Abstract:

    Development of the retinotectal system in the direct-developing frog Eleutherodactylus coqui in comparison with other anuran

  • mosaic evolution of neural development in anurans acceleration of spinal cord development in the direct developing frog Eleutherodactylus coqui
    Anatomy and Embryology, 2003
    Co-Authors: Gerhard Schlosser
    Abstract:

    Previous studies have shown that spinal cord development in direct developing frogs of the genus Eleutherodactylus, which have evolutionarily lost the tadpole stage, differs from that in biphasically developing anurans (with the larval and the adult stage separated by metamorphosis). The present study of spinal cord development in Eleutherodactylus coqui provides additional information about neurogenesis, neuronal differentiation and growth analyzed by immunostaining for proliferating cell nuclear antigen (PCNA), in situ hybridization for NeuroD, and morphometric measurements in various developmental stages. Furthermore, spinal cord development in the frogs Discoglossus pictus, Xenopus laevis, and Physalaemus pustulosus, which belong to different anuran families but all exhibit biphasic development, was similarly analyzed. This comparative analysis allows inference of the ancestral anuran pattern of spinal cord development and how it has been modified during the evolution of Eleutherodactylus. All biphasically developing frogs analyzed share a similar pattern of spinal cord development, suggesting that this is ancestral for anurans: after neural tube closure, levels of proliferation and neurogenesis in the spinal cord were low throughout embryogenesis until they were upregulated drastically at early larval stages followed by development of the lateral motor columns. In contrast, no such quiescent embryonic period exists in E. coqui, where rapid growth, high levels of proliferation and neurogenesis, and early formation of lateral motor columns occur shortly after neural tube closure, while other parts of the central nervous system develop more slowly. Thus, spinal cord development has been accelerated during the evolution of Eleutherodactylus relative to the development of other parts of the central nervous system, probably related to the precocious development of limbs in this lineage.

  • development of the retina is altered in the directly developing frog Eleutherodactylus coqui leptodactylidae
    Neuroscience Letters, 1997
    Co-Authors: Gerhard Schlosser, Gerhard Roth
    Abstract:

    The loss of a free-living larval stage during the evolution of directly developing frogs of the genus Eleutherodactylus resulted in dramatic alterations in ontogeny. Immunostaining for proliferating cell nuclear antigen reveals that in the directly developing frog Eleutherodactylus coqui pervasive cell proliferation occurs throughout the retina even after the plexiform layers have formed. In striking contrast to biphasically developing frogs (e.g. Discoglossus pictus or Xenopus laevis), in E. coqui proliferation becomes restricted to the ciliary margin only after the eye has reached the size typical of a postmetamorphic froglet and after its laminar structure has developed. As a consequence, the retina of E. coqui develops rapidly without recapitulating larva-typical stages. Our results suggest that dissociation of cell proliferation and differentiation can lead to the abbreviation of ontogenies during evolution.

Mueses-cisneros, Jonh Jairo - One of the best experts on this subject based on the ideXlab platform.

Blair S Hedges - One of the best experts on this subject based on the ideXlab platform.

  • eleutherodactyline frogs anura leptodactylidae from the cordillera yanachaga in central peru
    Copeia, 2005
    Co-Authors: William E Duellman, Blair S Hedges
    Abstract:

    A small collection of anurans from the Cordillera Yanachaga in central Peru revealed the presence of 10 species of Eleutherodactylus. Four of these species are unknown elsewhere and are described herein. Three of the new species are members of the immense Eleutherodactylus unistrigatus group, and one belongs with the smaller, South American Eleutherodactylus conspicillatus group. The 83 described species of Eleutherodactylus known in Peru belong to six species groups that have different patterns of distribution. Most species in the cloud forest in the Cordillera Oriental, Cordillera Central, and associated ranges have small latitudinal and elevational distributions.

  • a new grass frog from pine forests of western cuba and description of acoustic and pattern variation in Eleutherodactylus varleyi amphibia leptodactylidae
    2003
    Co-Authors: Blair S Hedges
    Abstract:

    A new frog of the genus Eleutherodactylus is described from pine forests of Alturas de Pizarras del Sur, Province of Pinar del Ro ´o, Cuba. It is most closely related to the widely distributed Cuban species E. varleyi Dunn, with which it occurs sympatrically, but differs in several morphological and acous- tical characters. Variation in the advertisement call and color pattern of E. varleyi are described.

  • rapid chromosome evolution in jamaican frogs of the genus Eleutherodactylus leptodactylidae
    Journal of Zoology, 1995
    Co-Authors: James P Bogart, Blair S Hedges
    Abstract:

    Chromosomes from all 17 species of native Jamaican Eleutherodactylus as well as introduced E. johnstonei were subjected to computer-assisted analyses. Diploid chromosome numbers of 24, 26, 28, 30 and 32 were found and no two species had identical karyotypes. Karyotypic data were superimposed on a phylogeny derived from allozyme and immunological data in order to assess karyotypic changes that occurred in lineages of Jamaican Eleutherodactylus. Chromosome number changes have occurred at least nine times on the island and have involved both fission and fusion mutational events. C-bands and the sites of secondary constrictions varied and provide very little phylogenetic information. In most instances, karyotypically determined interspecific evolutionary relationships corresponded with the molecular data. The combination of karyological analyses and molecular data clarified lineages which involved convergent chromosome numbers or extremely divergent karyotypes. Karyotypic changes in Jamaican Eleutherodactylus are best explained by chromosome fission, fusion, translocations and inversions which arose in isolated demes and have been fixed through inbreeding and genetic drift. Rates of karyotypic evolution among Jamaican Eleutherodactylus are much faster than previous published rates for frogs. Karyotypic evolution appears to be dictated by behavioural factors and effective population sizes irrespective of taxonomic groupings.

  • albumin evolution in west indian frogs of the genus Eleutherodactylus leptodactylidae caribbean biogeography and a calibration of the albumin immunological clock
    Journal of Zoology, 1991
    Co-Authors: Carla Ann Hass, Blair S Hedges
    Abstract:

    Antisera to serum albumins from five West Indian species of the frog genus Eleutheroductylus were prepared, and the reciprocal immunological distances (IDs) obtained were used to provide a time frame for the evolution of this group in the West Indies. One-way IDS were obtained to 25 additional species within the genus, with emphasis on those from the West Indies. These immunological data support both a recent classification of Eleutheroductylus based on an analysis of slow-evolving allozyme loci, and the monophyly of the 17 native Jamaican species as indicated by a more comprehensive electrophoretic study. This is in contrast to the results of morphological studies supporting multiple invasions of Jamaica by Eleutherodactylus. Within the subgenus Euhyas, IDS ranged from6–27 between Jamaican species, whereas between species on different islands the range was29–67. The subgenus Syrrhophus in southern North America was found to be the sister group to the subgenus Euhyus, a western Caribbean clade. Pelorius, a subgenus restricted to Hispaniola, was found to be the sister group of the subgenus Eleutheroductylus in the West Indies. The largest IDs obtained for West Indian species were those between the two major groups, the subgenera Eleutheroductylus and Euhyas. The albumin immunological clock for Eleutheroductylus was calibrated with three events in the geologic history of the Caribbean: the breakup of the proto-Antilles (65-75 million years before present [mybp]), the emergence of Jamaica (20-30 mybp), and the uplift of the Blue Mountains in Jamaica (5-10 mybp). Immunological distances corresponding to those events yield a calibration of 1 ID=0.60 million years (my), the same as that previously obtained for other groups of amphibians and thus supports the use of albumin immunological distance as a molecular chronometer in the genus Eleutherodactylus