2003. Cranial ontogeny of Lutreolina crassicaudata (Didelphidae): a comparison with Didelphis alb... more 2003. Cranial ontogeny of Lutreolina crassicaudata (Didelphidae): a comparison with Didelphis albiventris. Acta Theriologica 48: 1-9.
sysTemaTics and disTriBuTion of marsuPials in argenTina: a revieW una revisión de la sisTemáTica ... more sysTemaTics and disTriBuTion of marsuPials in argenTina: a revieW una revisión de la sisTemáTica y disTriBución de los marsuPiales de argenTina David a. Flores, M. Mónica Díaz, and rubén M. Barquez
Este volumen de Fieldiana Zoology comprende una muy completa compilación de localidades puntuales... more Este volumen de Fieldiana Zoology comprende una muy completa compilación de localidades puntuales de distribución de los marsupiales vivientes del Neotrópico. Sin duda se trata de un gran esfuerzo de recopilación bibliográfica y de material depositado en colecciones sistemáticas. De acuerdo a la autora, este proyecto se inicio en 1992 bajo la dirección del desaparecido Philip Hershkovitz. El trabajo cuenta con una lista de especies bastante actualizada, respecto de los recientes avances en taxonomía, sistemática y distribución de los marsupiales neotropicales. Se incluyen 76 especies en la familia Didelphidae, 6 especies en la familia Caenolestidae, y una especie en la familia Microbiotheriidae. Por otro lado se presentan 98 mapas de distribución puntual de géneros y especies, donde se exponen localidades ya publicadas y algunos registros novedosos no publicados. Uno de los aportes más importantes de la presente revisión es el la muy completa Gazeteer lista de localidades en el Neotrópico, en su gran mayoría con referencias de coordenadas geográficas, que fueron obtenidas de mapas y trabajos publicados, indicándose además en cada una, las especies presentes en cada localidad. Por otra parte, el trabajo muestra un aceptable manejo de la sinonimia, lo que indica un esfuerzo de revisión de la literatura.
sysTemaTics and disTriBuTion of marsuPials in argenTina: a revieW una revisión de la sisTemáTica ... more sysTemaTics and disTriBuTion of marsuPials in argenTina: a revieW una revisión de la sisTemáTica y disTriBución de los marsuPiales de argenTina David a. Flores, M. Mónica Díaz, and rubén M. Barquez
Phylogenetic analysis of a fragment of the mitochondrial genome and qualitative and quantitative ... more Phylogenetic analysis of a fragment of the mitochondrial genome and qualitative and quantitative assessments of morphological variation suggest that, in its current conception, Thylamys pusillus (Desmarest, 1804) is a complex of at least three species. In the taxonomic arrangement proposed in this work, the populations in the Argentinean provinces of Entre Ríos and Corrientes are here referred to T. citellus , while the small Thylamys that lives in the Argentinean Dry Chaco are provisionally referred to T. pulchellus . In our scheme, Thylamys pusillus is restricted to the Bolivian and Paraguayan Chaco and the vicinities of northern Formosa province in Argentina. We provide emended diagnosis for T. citellus and T. pulchellus, together with detailed morphological descriptions and discuss their distinctiveness from other species of Thylamys. In addition, we included new distributional data.
Cranial suture closure and its bilateral asymmetry in the franciscana dolphin, Pontoporia blainvi... more Cranial suture closure and its bilateral asymmetry in the franciscana dolphin, Pontoporia blainvil-lei, were studied. Our results showed that the closure of cranial sutures exhibit low variability associated to total body size, with the exception of the premaxilla-maxilla suture which showed some correlation with body size. The cranial sutures of franciscana dolphins showed closure with no directional asymmetry, in accordance with the results found in dolphin species studied to date. Our results support the idea that different species of dolphins exhibit distinct patterns of suture closure, associated with their specific evolutionary histories and functional demands, and that there is no general common pattern. RESUMEN. Fusión de suturas craneales en el delfín franciscana, Pontoporia blainvillei (Gervais and D'Orbigny, 1844). Se estudió la fusión de suturas craneales y su asimetría bilateral en el delfín franciscana, Pontoporia blainvillei. Nuestros resultados mostraron que el c...
The taxonomic identities of populations of Philander Brisson of Argentina are still unclear. Phil... more The taxonomic identities of populations of Philander Brisson of Argentina are still unclear. Philander frenatus (Olfers) is the only species assigned to the country, a conclusion based on incomplete analysis of available material and without a clear taxonomic criterion. The aim of this study was to determine the taxonomic identity of the populations of Philander of Argentina. To accomplish this, DNA from eight specimens from Argentina and one specimen from Paraguay was sequenced and compared with sequences published by other authors, using a phylogenetic approach. To complement the molecular information, seven skull measurements were taken from specimens of P. frenatus and P. opossum canus (Osgood) from Bolivia and Brazil, and compared with the specimens from Argentina and Paraguay using bi- and multivariate analyses. Molecular and morphological results showed that there are two species of Philander in Argentina, P. frenatus in Misiones province and P. opossum canus in Chaco and For...
We report a list of species of bats occurring in Belo Horizonte, the capital of Minas Gerais stat... more We report a list of species of bats occurring in Belo Horizonte, the capital of Minas Gerais state, southeastern Brazil. We recorded 16 species belonging to three families,Vespertilionidae, Molossidae, and Phyllostomidae. Artibeus lituratus was by far the most abundant species, representing 70% of the captures. Remnants of native vegetation in urban parks as well as the urban arborization which frequently includes chiropterocoric or chiropterophilous species, as well as the illumination that attracts a great range of insects and houses and buildings also attract and maintain a quite rich assemblage of bats living in Belo Horizonte. Roost search seems to be the most effective method to find mollosids that would not be recorded by mist netting.
Cetaceans swim by the alternate action of their epiaxial and hypaxial muscles and their propulsiv... more Cetaceans swim by the alternate action of their epiaxial and hypaxial muscles and their propulsive movements are confined to the vertical plane. Changes in the shape and mechanical properties of vertebrae strongly affect their function during oscillatory swimming. The first objective of this study was to provide a quantitative characterization of vertebral morphology in representatives of the Delphinidae and Pontoporiidae families. A novel morphometric approach was applied, using nine vertebral measurements and three indices. The second objective was to assess the relationship between morphology and both habitat and size through regression analyses. The phylogenetic structure of the distribution of characters was also explored by estimating phylogenetic signal. No relationship was found between morphology and habitat or size, but vertebral measurements and indices showed a significant phylogenetic signal. Morphological profiles indicated that coastal and oceanic delphinid species ha...
The diversity of items consumed by modern didelphids, varying from mostly fruits in Caluromys All... more The diversity of items consumed by modern didelphids, varying from mostly fruits in Caluromys Allen to mostly small vertebrates in Lutreolina O. Thomas, may cause changes in molar size and shape. We evaluated the morphometric variation of the first and third upper and lower molars of 16 genera of didelphid marsupials, with the aim of assessing the relationship between molar shape change, diet and phylogeny. We used a geometric morphometric approach to analyse how shape changes with diet. We mapped shape onto the phylogeny of the group to reconstruct ancestral states and analyse the evolution of molar shape. Finally, we statistically estimated the effect of size, diet and phylogeny on molar shape. All the analyses indicated little correlation between diet and molar shape and a strong correlation between the position of each genus on the phylogeny and molar shape. We believe that the wide ecological niche used by most of the groups (at least regarding diet) makes the evolutionary changes not strong enough to override pre-existing differences that occur among clades, and the absence of highly dietspecialized species (e.g. hypercarnivory or obligate folivory) causes the need for retaining a molar shape that can be useful to process different kinds of food items.
The patterns of development and skull ontogeny in caenolestids have been poorly studied, resultin... more The patterns of development and skull ontogeny in caenolestids have been poorly studied, resulting in a limited knowledge. In this work, we report and compare the allometric growth trends of 15 variables in the three living groups of the Family Caenolestidae, represented by Caenolestes fuliginosus, Lestoros inca, and Rhyncholestes raphanurus. We analyzed the bivariate and multivariate allometry in comparison with morphologically convergent Australasian peramelids, as well as with other marsupials and placentals previously studied. We also report the phylogenetic signal and optimization of the confidence intervals of the variables analyzed in two alternative hypotheses, where Ameridelphia is considered as monophyletic and paraphyletic. Rhyncholestes raphanurus and C. fuliginosus shared more allometric trends than any other between-taxa comparisons. Notwithstanding, several statistics were higher in R. raphanurus, except for those variables related to temporal muscles and bite. The close relationship between R. raphanurus and L. inca is also supported by the longitudinal growth of the rostrum, although with a clear growth extension in R. raphanurus. The allometric trends reported for L. inca reflect a more predaceous condition compared to other caenolestids. Bandicoots and caenolestids did not show a particularly shared growth pattern, with the latter being morphologically more conservative. Ameridelphia was paraphyletic in the shortest tree regarding the optimization of the confidence intervals. However, the growth of several variables supported monophyletic groups in both hypotheses. Skull ontogeny in marsupials is informative in several aspects of the mandible and neurocranium reflecting the high phylogenetic signal displayed by variables related to these cranial regions. coronoid process, LD Length of the dentary, LN Length of the nasals, LP Lower postcanine toothrow, MH Muzzle height, ORB Orbit length, PAL Palate length, UP Upper postcanine toothrow, ZB Zygomatic breadth J Mammal Evol
The aim of this work was to study the postnatal ontogenetic development of Pontoporia blainvillei... more The aim of this work was to study the postnatal ontogenetic development of Pontoporia blainvillei skull, identifying major changes on shape, and relating them to relevant factors in the life history of the species. We analyzed a complete ontogenetic series (73♂, 83♀) with three-dimensional geometric morphometric techniques. Immature dolphins showed a very well-developed braincase and a poorly developed rostrum, and the principal postnatal changes affected the rostrum and the temporal fossa, both structures implied functionally to the feeding apparatus, thus suggesting a specialized mode for catch fast prey in P. blainvillei. Osseous elements associated with sound production were already well developed on immature dolphins, suggesting the importance of this apparatus since the beginning of postnatal life. Sexual dimorphism was detected on both shape and size variables. Females were bigger than males, in accordance with previous studies. Shape differences between sexes were found on t...
2003. Cranial ontogeny of Lutreolina crassicaudata (Didelphidae): a comparison with Didelphis alb... more 2003. Cranial ontogeny of Lutreolina crassicaudata (Didelphidae): a comparison with Didelphis albiventris. Acta Theriologica 48: 1-9.
sysTemaTics and disTriBuTion of marsuPials in argenTina: a revieW una revisión de la sisTemáTica ... more sysTemaTics and disTriBuTion of marsuPials in argenTina: a revieW una revisión de la sisTemáTica y disTriBución de los marsuPiales de argenTina David a. Flores, M. Mónica Díaz, and rubén M. Barquez
Este volumen de Fieldiana Zoology comprende una muy completa compilación de localidades puntuales... more Este volumen de Fieldiana Zoology comprende una muy completa compilación de localidades puntuales de distribución de los marsupiales vivientes del Neotrópico. Sin duda se trata de un gran esfuerzo de recopilación bibliográfica y de material depositado en colecciones sistemáticas. De acuerdo a la autora, este proyecto se inicio en 1992 bajo la dirección del desaparecido Philip Hershkovitz. El trabajo cuenta con una lista de especies bastante actualizada, respecto de los recientes avances en taxonomía, sistemática y distribución de los marsupiales neotropicales. Se incluyen 76 especies en la familia Didelphidae, 6 especies en la familia Caenolestidae, y una especie en la familia Microbiotheriidae. Por otro lado se presentan 98 mapas de distribución puntual de géneros y especies, donde se exponen localidades ya publicadas y algunos registros novedosos no publicados. Uno de los aportes más importantes de la presente revisión es el la muy completa Gazeteer lista de localidades en el Neotrópico, en su gran mayoría con referencias de coordenadas geográficas, que fueron obtenidas de mapas y trabajos publicados, indicándose además en cada una, las especies presentes en cada localidad. Por otra parte, el trabajo muestra un aceptable manejo de la sinonimia, lo que indica un esfuerzo de revisión de la literatura.
sysTemaTics and disTriBuTion of marsuPials in argenTina: a revieW una revisión de la sisTemáTica ... more sysTemaTics and disTriBuTion of marsuPials in argenTina: a revieW una revisión de la sisTemáTica y disTriBución de los marsuPiales de argenTina David a. Flores, M. Mónica Díaz, and rubén M. Barquez
Phylogenetic analysis of a fragment of the mitochondrial genome and qualitative and quantitative ... more Phylogenetic analysis of a fragment of the mitochondrial genome and qualitative and quantitative assessments of morphological variation suggest that, in its current conception, Thylamys pusillus (Desmarest, 1804) is a complex of at least three species. In the taxonomic arrangement proposed in this work, the populations in the Argentinean provinces of Entre Ríos and Corrientes are here referred to T. citellus , while the small Thylamys that lives in the Argentinean Dry Chaco are provisionally referred to T. pulchellus . In our scheme, Thylamys pusillus is restricted to the Bolivian and Paraguayan Chaco and the vicinities of northern Formosa province in Argentina. We provide emended diagnosis for T. citellus and T. pulchellus, together with detailed morphological descriptions and discuss their distinctiveness from other species of Thylamys. In addition, we included new distributional data.
Cranial suture closure and its bilateral asymmetry in the franciscana dolphin, Pontoporia blainvi... more Cranial suture closure and its bilateral asymmetry in the franciscana dolphin, Pontoporia blainvil-lei, were studied. Our results showed that the closure of cranial sutures exhibit low variability associated to total body size, with the exception of the premaxilla-maxilla suture which showed some correlation with body size. The cranial sutures of franciscana dolphins showed closure with no directional asymmetry, in accordance with the results found in dolphin species studied to date. Our results support the idea that different species of dolphins exhibit distinct patterns of suture closure, associated with their specific evolutionary histories and functional demands, and that there is no general common pattern. RESUMEN. Fusión de suturas craneales en el delfín franciscana, Pontoporia blainvillei (Gervais and D'Orbigny, 1844). Se estudió la fusión de suturas craneales y su asimetría bilateral en el delfín franciscana, Pontoporia blainvillei. Nuestros resultados mostraron que el c...
The taxonomic identities of populations of Philander Brisson of Argentina are still unclear. Phil... more The taxonomic identities of populations of Philander Brisson of Argentina are still unclear. Philander frenatus (Olfers) is the only species assigned to the country, a conclusion based on incomplete analysis of available material and without a clear taxonomic criterion. The aim of this study was to determine the taxonomic identity of the populations of Philander of Argentina. To accomplish this, DNA from eight specimens from Argentina and one specimen from Paraguay was sequenced and compared with sequences published by other authors, using a phylogenetic approach. To complement the molecular information, seven skull measurements were taken from specimens of P. frenatus and P. opossum canus (Osgood) from Bolivia and Brazil, and compared with the specimens from Argentina and Paraguay using bi- and multivariate analyses. Molecular and morphological results showed that there are two species of Philander in Argentina, P. frenatus in Misiones province and P. opossum canus in Chaco and For...
We report a list of species of bats occurring in Belo Horizonte, the capital of Minas Gerais stat... more We report a list of species of bats occurring in Belo Horizonte, the capital of Minas Gerais state, southeastern Brazil. We recorded 16 species belonging to three families,Vespertilionidae, Molossidae, and Phyllostomidae. Artibeus lituratus was by far the most abundant species, representing 70% of the captures. Remnants of native vegetation in urban parks as well as the urban arborization which frequently includes chiropterocoric or chiropterophilous species, as well as the illumination that attracts a great range of insects and houses and buildings also attract and maintain a quite rich assemblage of bats living in Belo Horizonte. Roost search seems to be the most effective method to find mollosids that would not be recorded by mist netting.
Cetaceans swim by the alternate action of their epiaxial and hypaxial muscles and their propulsiv... more Cetaceans swim by the alternate action of their epiaxial and hypaxial muscles and their propulsive movements are confined to the vertical plane. Changes in the shape and mechanical properties of vertebrae strongly affect their function during oscillatory swimming. The first objective of this study was to provide a quantitative characterization of vertebral morphology in representatives of the Delphinidae and Pontoporiidae families. A novel morphometric approach was applied, using nine vertebral measurements and three indices. The second objective was to assess the relationship between morphology and both habitat and size through regression analyses. The phylogenetic structure of the distribution of characters was also explored by estimating phylogenetic signal. No relationship was found between morphology and habitat or size, but vertebral measurements and indices showed a significant phylogenetic signal. Morphological profiles indicated that coastal and oceanic delphinid species ha...
The diversity of items consumed by modern didelphids, varying from mostly fruits in Caluromys All... more The diversity of items consumed by modern didelphids, varying from mostly fruits in Caluromys Allen to mostly small vertebrates in Lutreolina O. Thomas, may cause changes in molar size and shape. We evaluated the morphometric variation of the first and third upper and lower molars of 16 genera of didelphid marsupials, with the aim of assessing the relationship between molar shape change, diet and phylogeny. We used a geometric morphometric approach to analyse how shape changes with diet. We mapped shape onto the phylogeny of the group to reconstruct ancestral states and analyse the evolution of molar shape. Finally, we statistically estimated the effect of size, diet and phylogeny on molar shape. All the analyses indicated little correlation between diet and molar shape and a strong correlation between the position of each genus on the phylogeny and molar shape. We believe that the wide ecological niche used by most of the groups (at least regarding diet) makes the evolutionary changes not strong enough to override pre-existing differences that occur among clades, and the absence of highly dietspecialized species (e.g. hypercarnivory or obligate folivory) causes the need for retaining a molar shape that can be useful to process different kinds of food items.
The patterns of development and skull ontogeny in caenolestids have been poorly studied, resultin... more The patterns of development and skull ontogeny in caenolestids have been poorly studied, resulting in a limited knowledge. In this work, we report and compare the allometric growth trends of 15 variables in the three living groups of the Family Caenolestidae, represented by Caenolestes fuliginosus, Lestoros inca, and Rhyncholestes raphanurus. We analyzed the bivariate and multivariate allometry in comparison with morphologically convergent Australasian peramelids, as well as with other marsupials and placentals previously studied. We also report the phylogenetic signal and optimization of the confidence intervals of the variables analyzed in two alternative hypotheses, where Ameridelphia is considered as monophyletic and paraphyletic. Rhyncholestes raphanurus and C. fuliginosus shared more allometric trends than any other between-taxa comparisons. Notwithstanding, several statistics were higher in R. raphanurus, except for those variables related to temporal muscles and bite. The close relationship between R. raphanurus and L. inca is also supported by the longitudinal growth of the rostrum, although with a clear growth extension in R. raphanurus. The allometric trends reported for L. inca reflect a more predaceous condition compared to other caenolestids. Bandicoots and caenolestids did not show a particularly shared growth pattern, with the latter being morphologically more conservative. Ameridelphia was paraphyletic in the shortest tree regarding the optimization of the confidence intervals. However, the growth of several variables supported monophyletic groups in both hypotheses. Skull ontogeny in marsupials is informative in several aspects of the mandible and neurocranium reflecting the high phylogenetic signal displayed by variables related to these cranial regions. coronoid process, LD Length of the dentary, LN Length of the nasals, LP Lower postcanine toothrow, MH Muzzle height, ORB Orbit length, PAL Palate length, UP Upper postcanine toothrow, ZB Zygomatic breadth J Mammal Evol
The aim of this work was to study the postnatal ontogenetic development of Pontoporia blainvillei... more The aim of this work was to study the postnatal ontogenetic development of Pontoporia blainvillei skull, identifying major changes on shape, and relating them to relevant factors in the life history of the species. We analyzed a complete ontogenetic series (73♂, 83♀) with three-dimensional geometric morphometric techniques. Immature dolphins showed a very well-developed braincase and a poorly developed rostrum, and the principal postnatal changes affected the rostrum and the temporal fossa, both structures implied functionally to the feeding apparatus, thus suggesting a specialized mode for catch fast prey in P. blainvillei. Osseous elements associated with sound production were already well developed on immature dolphins, suggesting the importance of this apparatus since the beginning of postnatal life. Sexual dimorphism was detected on both shape and size variables. Females were bigger than males, in accordance with previous studies. Shape differences between sexes were found on t...
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