Pigment composition of the bright skin in the poison toad, Melanophryniscus rubriventris (Anura: Bufonidae) from Argentina

The determination of the basis of skin colour is important to better understand the evolutionary and ecological relevance of colour variation in aposematic species. Significant variation in bright skin colouration can be found between and within populations of the poison toad, Melanophryniscus rubriventris. In this study, we identified the pigments present in the skin in seven populations of the species in Argentina to determine pigment composition of bright colouration. Our analysis showed that at least four different primary pigments consisting of a suite of orange-red carotenes and yellow xanthophylls contribute to the bright skin colour in different populations of the species. Four carotenoids, Astaxanthin, β-Carotene, Canthaxanthin, and Lycopene were detected by comparison with available standards in skin tissues on each population. Four carotenoids were also detected but not identified. We provide evidence that differences in colouration between individuals and populations in Melanophryniscus rubriventris cannot be merely ascribed to differences in their skin pigment profiles (i.e. pigment types). We discuss alternative explanations and stress the need of more studies on complex mechanisms and interactions affecting the expression of skin colouration in poison frogs and toads.Fil: Bonansea, Maria Ines. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Heit, Cecilia. Universidad Nacional de Jujuy; ArgentinaFil: Vaira, Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Jujuy. Universidad Nacional de Jujuy. Centro de Investigaciones y Transferencia de Jujuy; Argentin

Reptilia, Squamata, Dipsadidae, Tomodon orestes Harvey and Muñoz, 2004: distribution extension, new country record

We report the first record of Tomodon orestes Harvey and Muñoz, 2004 for Argentina. An adult male was collected in November 2008 in an open grassland habitat in the locality of Vallecito, Santa Victoria department, Salta province, Argentina. This new record is the southernmost locality for the species extending its distribution range ca. 95 km straight-line south from type locality

Geographic and intrapopulational variation in colour and patterns of an aposematic toad, Melanophryniscus rubriventris (Amphibia, Anura, Bufonidae)

The aposematic toad genus Melanophryniscus is a polymorphic group with noticeable variation in colour and pattern. Here, we objectively evaluate variation in spectral reflectance and quantify variation in patterning within and among populations of the species M. rubriventris in NW Argentina. We conducted spectrophotometric analysis on 69 individuals and recorded dorsal and ventral pattern morphs of 727 individuals from six populations. We found high divergence in the reflectance spectra, the extent of brightly coloured areas, and the skin alkaloid profiles with no correlation among coloration varieties, alkaloid profiles, and the geographic distance between populations. Our analyses imply subdivision of sampled populations groupings based mostly on different dorsal colorations. Our results also reveal that populations with very similar patterns may differ markedly in colour and vice versa. It is striking that these aposematic toads show a pronounced variation in colour and patterning among and within populations showing individuals with a conspicuous bright dorsal colouration but also morphs with a rather cryptic black or drab colouration. However, the known presence of several alkaloids classes in all populations suggests that all morphs might be equally unpalatable.Fil: Bonansea, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Vaira, Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentin

Soundscapes of the Yungas Andean forest: Identifying the acoustic footprint of an anuran assemblage

Soundscapes are composed by the conjunction of sound patterns in each space and time. The biophony produced by the advertisement calls of anurans are one of the most outstanding features of a soundscape, particularly in subtropical montane areas such as the Yungas Andean forests of NW Argentina. We recorded soundscapes with automated recording units along an altitudinal gradient and throughout a whole year in the Calilegua National Park. Using a novel combination of visual analysis and acoustic indices we have been able to identify the anuran acoustic fingerprint in the soundscapes of a seasonal subtropical montane forest. In addition, we detected a decrement in using the acoustic communication channel along the altitudinal gradient by anuran assemblages, in agreement with a decrement in species richness. Our results showed a seasonal effect of the vocalization patterns, splitting the group of sounds recorded in two main periods along the year. In this study we presented the first description of Argentina's altitudinal strata of the Yungas Andean forests. This information provides a solid basis for monitoring programs of direct and indirect anthropogenic impacts. Additionally, we highlight the importance of understanding how soundscapes are composed in a naturally protected area and, posit them as a novel ecosystem service that could benefit human health. We emphasise that Natural Soundscapes should be protected and must be included as intangible heritage in the management plans of protected areas in the country. Likewise, the methods proposed in this study encourage settling down the basis for implementing long-term acoustic monitoring of anuran species and other acoustic communities in the Yungas ecoregion.Fil: Boullhesen, Martin. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Vaira, Marcos. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Barquez, Ruben Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Programa de Investigación de Biodiversidad Argentina; ArgentinaFil: Akmentins, Mauricio Sebastián. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentin

Análisis comparativo de la estructura del canto del anuncio de tres poblaciones de <i>Melanophryniscus rubriventris</i> (Vellar, 1947) (Anura: Bufonidae)

La estructura de la señal acústica en anuros ha sido considerada especie-específica y utilizada incluso para el reconocimiento de nuevas especies indistinguibles por caracteres morfológicos. En este trabajo, presentamos una descripción de la estructura del canto de Melanophryniscus rubriventris y un análisis comparativo de parámetros espectrales y temporales del canto de anuncio en tres poblaciones argentinas, cada una de ellas asignadas a una de las tres subespecies tradicionalmente reconocidas. El canto de anuncio emitido por los machos de M. rubriventris puede describirse como un trino agudo formado por dos segmentos: el primero está compuesto por una serie de emisiones cortas, aisladas y no pulsadas seguidas por el segundo segmento que conforma un trino rápido con una frecuencia constante de pulsos. La estructura del canto en dos segmentos coincide con las descripciones realizadas para otras cinco especies del género, pero difiere en los componentes temporales y espectrales. Las comparaciones de los cantos de las distintas poblaciones estudiadas de M. rubriventris no revelan ninguna diferencia significativa. Estas evidencias no parecen sustentar la existencia de subespecies ni que se deban efectuar cambios en el status específico de las poblaciones argentinas.The structure of the acoustic signal in anurans has been considered species-specific and used even for the recognition of new indistinguishable species by morphologic characters. In this work, we presented a description of the structure of the call ofMelanophryniscus rubriventris and a comparative analysis of spectral and temporal parameters of the advertisement call in three Argentine populations assigned to three traditionally recognized subspecies. The call emitted by males of M. rubriventris can be described like an acute trill formed by two segments: a first segment with a series of short, unpulsed isolated emissions followed by the second segment: a fast trill of a constant frequency of pulses. The structure of the call in two segments agrees with the descriptions made for other five species of the genus, but it differs in the temporal and spectral components. The call of the different studied populations from M. rubriventris does not reveal any significant difference. These evidences do not seem to sustain the existence of subspecies, or changes in the specific status of the Argentine populations.Asociación Herpetológica Argentina (AHA

Análisis comparativo de la estructura del canto del anuncio de tres poblaciones de <i>Melanophryniscus rubriventris</i> (Vellar, 1947) (Anura: Bufonidae)

La estructura de la señal acústica en anuros ha sido considerada especie-específica y utilizada incluso para el reconocimiento de nuevas especies indistinguibles por caracteres morfológicos. En este trabajo, presentamos una descripción de la estructura del canto de Melanophryniscus rubriventris y un análisis comparativo de parámetros espectrales y temporales del canto de anuncio en tres poblaciones argentinas, cada una de ellas asignadas a una de las tres subespecies tradicionalmente reconocidas. El canto de anuncio emitido por los machos de M. rubriventris puede describirse como un trino agudo formado por dos segmentos: el primero está compuesto por una serie de emisiones cortas, aisladas y no pulsadas seguidas por el segundo segmento que conforma un trino rápido con una frecuencia constante de pulsos. La estructura del canto en dos segmentos coincide con las descripciones realizadas para otras cinco especies del género, pero difiere en los componentes temporales y espectrales. Las comparaciones de los cantos de las distintas poblaciones estudiadas de M. rubriventris no revelan ninguna diferencia significativa. Estas evidencias no parecen sustentar la existencia de subespecies ni que se deban efectuar cambios en el status específico de las poblaciones argentinas.The structure of the acoustic signal in anurans has been considered species-specific and used even for the recognition of new indistinguishable species by morphologic characters. In this work, we presented a description of the structure of the call ofMelanophryniscus rubriventris and a comparative analysis of spectral and temporal parameters of the advertisement call in three Argentine populations assigned to three traditionally recognized subspecies. The call emitted by males of M. rubriventris can be described like an acute trill formed by two segments: a first segment with a series of short, unpulsed isolated emissions followed by the second segment: a fast trill of a constant frequency of pulses. The structure of the call in two segments agrees with the descriptions made for other five species of the genus, but it differs in the temporal and spectral components. The call of the different studied populations from M. rubriventris does not reveal any significant difference. These evidences do not seem to sustain the existence of subspecies, or changes in the specific status of the Argentine populations.Asociación Herpetológica Argentina (AHA

Disentangling the multiple components of anuran diversity associated to different land-uses in Yungas forests, Argentina

Natural habitats have drastically regressed due to rapid changes in land-use during recent decades, generating a decrease in species diversity. In light of natural habitat destruction worldwide, there is a need to adopt an integrative approach to the study of biodiversity in order to better assess the magnitude of diversity loss in landscapes affected by human intervention. The aim of this study was to assess and compare anuran assemblages under different land-uses in a subtropical forest of NW Argentina using an integrative view of diversity through different measures. We assessed alpha and beta diversity components for three complementary diversity measures: species richness, functional diversity and phylogenetic diversity in three land-uses: forest, tobacco and suburban. We carried out generalized linear mixed models with an autocorrelation structure to compare the three diversity measures across the different land-uses. We also used a beta diversity partitioning method to determine nestedness and turnover processes in taxonomic, functional and phylogenetic dissimilarity. Our results suggest a filtering effect of the land-uses on the diversity of anuran assemblages in the surveyed area, with an increased loss of anuran diversity in areas with intensified land-use, such as tobacco monoculture. This study contributes to understand amphibian communities associated to modified habitats in the Southern Andean Yungas forests from Argentina. Our findings highlight the importance of disentangling each diversity component separately to detect more accurately the diversity patterns associated to land-use change.Fil: Pereyra, Laura Cecilia. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina. Universidad Nacional de Jujuy; ArgentinaFil: Akmentins, Mauricio Sebastián. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina. Universidad Nacional de Jujuy; ArgentinaFil: Vaira, Marcos. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina. Universidad Nacional de Jujuy; ArgentinaFil: Moreno Ortega, Claudia Elizabeth. Universidad Autónoma del Estado de Hidalgo; Méxic

El estado de conservación de los anfibios en la República Argentina

Argentina alberga la décima fauna más grande de anfibios considerando los 40 países incluidos en la Región Neotropical y se encuentra entre los quince países que superan las 100 especies en esta región. Además, está incluida entre los veinte países con el 30% de sus especies consideradas endémicas (Bolaños et al., 2008; Lavilla y Heatwole 2010). Si bien todavía existe una importante falta de información para muchas de las especies de anfibios de Argentina, que incluye aspectos como la sistemática, genética, distribución, historia natural, ecología y comportamiento, las disminuciones informadas o inferidas y las amenazas identificadas para muchas de las especies requieren decisiones rápidas. En la República Argentina no existe en la actualidad un plan de acciones consensuadas entre los distintos organismos involucrados en el estudio y la conservación de los anfibios, ni que articule acciones entre el gobierno central y los estados provinciales. Sin embargo, la comunidad científica –principalmente- y algunos organismos gubernamentales en particular, llevan a cabo acciones concretas para describir e inventariar la diversidad de especies de anfibios y establecer su estado de conservación. La falta de un plan nacional consensuado puede provocar que algunas entidades involucradas en acciones de conservación adopten estrategias individuales que podrían no ser las más adecuadas o prioritarias para la situación actual de conservación de los anfibios de Argentina.Asociación Herpetológica Argentin

El estado de conservación de los anfibios en la República Argentina

Síntesis sobre ele stado de conservación de los anfibios en la República Argentina.Fil: Vaira, Marcos. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Akmentins, Mauricio Sebastián. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Lavilla, Esteban Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin

Alkaloids from single skins of the Argentinian toad Melanophryniscus rubriventris (ANURA, BUFONIDAE): An unexpected variability in alkaloid profiles and a profusion of new structures

GC-MS analysis of single-skins of ten Melanophryniscus rubriventris toads (five collections of two toads each) captured during their breeding season in NW Argentina has revealed a total of 127 alkaloids of which 56 had not been previously detected in any frog or toad. Included among these new alkaloids are 23 new diastereomers of previously reported alkaloids. What is particularly distinguishing about the alkaloid profiles of these ten collections is the occurrence of many of the alkaloids, whether known or new to us, in only one of the ten skins sampled, despite two skins being obtained from each breeding site of the five populations. Many of the alkaloids are of classes known to have structures with branched-chains (e.g. pumiliotoxins and tricyclic structures) that are considered to derive from dietary mites. A large number of previously reported and new alkaloids are also of unclassified structures. Only a very few 3,5-disubstituted-indolizidine or -pyrrolizidine alkaloids are observed that have a straight-chain carbon skeleton and are likely derived from ant prey. The possible relationship of these collections made during the toad’s brief breeding episodes to sequestration of dietary arthropods and individual alkaloid profiles is discussed.Fil: Garraffo, H. Martin. Laboratorio de Bioorganic Chemistry; Estados UnidosFil: Andriamaharavo, Nirina R.. Laboratorio de Bioorganic Chemistry; Estados UnidosFil: Vaira, Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina. Universidad Nacional de Jujuy. Facultad de Ingeniería; ArgentinaFil: Quiroga, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Jujuy. Universidad Nacional de Jujuy. Centro de Investigaciones y Transferencia de Jujuy; ArgentinaFil: Heit, Cecilia Inés. Laboratorio de Análisis de Residuos y Trazas; ArgentinaFil: Spande, Thomas F.. Laboratorio de Bioorganic Chemistry; Estados Unido