Books by Ricardo Montero
Hay dos versiones de este libro:-Versión optimizada para la lectura en computadora personal o imp... more Hay dos versiones de este libro:-Versión optimizada para la lectura en computadora personal o impresión en hojas A4 (Descargar aquí).-Versión optimizada para la lectura en teléfono celular (móvil) (Descargar aquí).
Autino, A. G. y Montero, R. 2012. Guía de Vertebrados de Bajo La Alumbrera, Catamarca, Argentina.... more Autino, A. G. y Montero, R. 2012. Guía de Vertebrados de Bajo La Alumbrera, Catamarca, Argentina. Minera Alumbrera Limited, 224 pp. Edición rústica: ISBN 978-987-28792-0-4; Edición cartoné: ISBN 978-987-28792-1-1.
Contiene información sobre las 93 especies más conspicuas de los Vertebrados de la región de Bajo De La Alumbrera (Catamarca, Argentina), incluyendo fotografías, dibujos, su descripción, distribución, biología y estado de conservación.
Es un compendio actualizado de la clasificación y las hipótesis filogenéticas más aceptadas de lo... more Es un compendio actualizado de la clasificación y las hipótesis filogenéticas más aceptadas de los vertebrados. Está dirigido a todos aquellos investigadores de la biología que necesitan conocer los nombres, distribuciones, clasificación y relaciones filogenéticas de los animales con los cuales trabaja, sobre todo en el cono sur y especialmente de Argentina.
Nota: hay una tercera edición (2018) más actualizada.
Papers by Ricardo Montero
Boletin De La Asociacion Herpetologica Argentina, 1988
Cuadernos De Herpetologia, 1986
Two new species of fossil Amphisbaena, A. braestrupi and A. laurenti, frorn the Pleistocene of La... more Two new species of fossil Amphisbaena, A. braestrupi and A. laurenti, frorn the Pleistocene of Lagoa Santa, Minas Gerais, Brazil, are described here. The morphology of the posterior part of their skulls suggests that they are rnost closely related to the extant A. alba.
Boletin De La Asociacion Herpetologica Argentina, 1985
Cuadernos De Herpetologia, 1996
Cuadernos De Herpetologia, 1996
Brasil y parte del Departamento Santa Cruz en Bolivia. Amphkbaena bolivica se distribuye en parte... more Brasil y parte del Departamento Santa Cruz en Bolivia. Amphkbaena bolivica se distribuye en parte del departamento Santa Cruz-y sur de Bolivia. en el sur de la región occidental de Paraguay y en toda la región chaqueña argentina; se distingue de la anterior por el número elevado de anillos del cuerpo y de la cola, número bajo de escamas alrededor de un anillo del medio del cuerpo y la pigmentación de la cabeza. Palabras clave: Reptilia, Squamata, Arnphisbaenia, Amphisbaenidae, Amphisbaena camura, Amphisbaena bolivim. What, until now. was considered as Amphisbaena camura Cope 1862 comprises in fact two distinct allopatnc taxa, the nominal form and Antphisbaena bolivica Mertens 1929. The geographic distribution of the nominal form. A. camura Cope, is restricted here to east and north Paraguay, Brazilian Mato
South American Journal of Herpetology, 2006
We report the first fossil record of the living amphisbaenian Amphisbaena heterozonata, from the ... more We report the first fossil record of the living amphisbaenian Amphisbaena heterozonata, from the Late Pleistocene of Buenos Aires province, Argentina. The specimen consists of a nearly complete skeleton, including cranium, coming from the Late Pleistocene Luján Formation, at the Altos Verdes Lake, Buenos Aires province, Argentina. The specimen is referred to Amphisbaena heterozonata on the basis of several cranial and postcranial morphological features, including an enlarged second maxillary tooth. This specimen constitutes the first fossil record of a living species of the family Amphisbaenidae in South America, and also the first fossil record for Amphisbaena heterozonata.
Sesamoids are elements that originate as intratendinous structures due to genetic and epigenetic ... more Sesamoids are elements that originate as intratendinous structures due to genetic and epigenetic factors. These elements have been reported frequently in vertebrates, although cranial sesamoids have been recorded almost exclusively in non-tetrapod Osteichthyes. The only tetrapod cranial sesamoids reported until now have been the transiliens cartilage (of crocodiles and turtles), and another one located in the quadrate-mandibular joint of birds. Here, we examined seven squamate species using histological sections, dissections of preserved specimens, dry skeletons, cleared and stained specimens, computed tomographies (CT), and report the presence of other cranial sesamoids. One is
attached to the cephalic condyle of the quadrate, embedded in the bodenaponeurosis and jaw adductor muscles of Ophiodes intermedius (Anguidae). The other sesamoid is found at the base of the basicranium of several squamates, capping the sphenoccipital tubercle, on the lateral side of the basioccipital–basisphenoid suture. This bone has previously been reported as “element X.” We reinterpret it as a basicranial sesamoid, as it is associated with tendons of the cranio-cervical muscles. This bone seems to have the function of resisting tension-compression forces generated by the muscle during flexion the head. This element was previously known in several squamates, and we
confirmed its presence in three additional squamate families: Gymnophthalmidae, Gekkonidae, and Pygopodidae. The evidence suggests that cranial sesamoids are a widespread character in squamates, and it is possible that this feature has been present since the origin of the group
Sesamoids are elements that originate as intratendinous structures due to genetic and epigenetic ... more Sesamoids are elements that originate as intratendinous structures due to genetic and epigenetic factors. These elements have been reported frequently in vertebrates, although cranial sesamoids have been recorded almost exclusively in non-tetrapod Osteichthyes. The only tetrapod cranial ses-amoids reported until now have been the transiliens cartilage (of crocodiles and turtles), and another one located in the quadrate-mandibular joint of birds. Here, we examined seven squamate species using histological sections, dissections of preserved specimens, dry skeletons, cleared and stained specimens, computed tomographies (CT), and report the presence of other cranial sesamoids. One is attached to the cephalic condyle of the quadrate, embedded in the bodenaponeurosis and jaw adductor muscles of Ophiodes intermedius (Anguidae). The other sesamoid is found at the base of the basicranium of several squamates, capping the sphenoccipital tubercle, on the lateral side of the basioccipital–basisphenoid suture. This bone has previously been reported as " element X. " We rein-terpret it as a basicranial sesamoid, as it is associated with tendons of the cranio-cervical muscles. This bone seems to have the function of resisting tension-compression forces generated by the muscle during flexion the head. This element was previously known in several squamates, and we confirmed its presence in three additional squamate families: Gymnophthalmidae, Gekkonidae, and Pygopodidae. The evidence suggests that cranial sesamoids are a widespread character in squa-mates, and it is possible that this feature has been present since the origin of the group.
Twelve species of birds have been reported to prey upon amphisbaenians (Squamata: Amphisbaenidae)... more Twelve species of birds have been reported to prey upon amphisbaenians (Squamata: Amphisbaenidae). We document the first report of predation on an amphisbaenian by a heron (Pelecaniformes: Ardeidae). On 1 November 2012 we photographed a Whistling Heron Syrigma sibilatrix preying on an Amphisbaena heterozonata at Tucumán, Argentina.
—I address some taxonomic issues created by previous perceptions of species' boundaries in Amphis... more —I address some taxonomic issues created by previous perceptions of species' boundaries in Amphisbaena from southern South America, including specimens with intermediate characteristics. In this note I propose the synonymization of Amphisbaena trachura and Amphisbaena heterozonata into Amphisbaena darwini, and the maintenance of the current species Amphisbaena angustifrons and Amphisbaena plumbea. RESUMEN.—Se encaran problemas taxon´omicos provocados por decisiones previas sobre algunas especies del cono sur de América del Sur, de las cuales existen ejemplares con características intermedias. Se propone que Amphisbaena trachura y Amphisbaena heterozonata se incluyan en la sinonimia de Amphisbaena darwini, y se propone mantener como especies válidas a Amphisbaena angustifrons y Amphisbaena plumbea.
We analyzed the prevalence of tail autotomy and regeneration in Teius teyou with the use of 640 m... more We analyzed the prevalence of tail autotomy and regeneration in Teius teyou with the use of 640 museum specimens. There is a marked difference in the prevalence of tail autotomy between juveniles (5.4%) and adults (23.9%); we found no significant differences in the prevalence between males and females. In contrast with the trends observed in other families, there exists an inverse relationship between the average size and the prevalence of autotomy among teiid species. We suggest that this could be explained by the important role played by the tail in locomotion, courtship, and defense of teiids. Alternatively, being a large species, these teiids may have an enhanced capacity for repelling attacks without losing their tails. Finally, we report a specimen that presented a bifid regenerated tail.
The Anatomical Record, 2016
The hylid genus Phyllomedusa comprises charismatic frogs commonly known as monkey, leaf or green ... more The hylid genus Phyllomedusa comprises charismatic frogs commonly known as monkey, leaf or green frogs, and is the most diverse genus of the subfamily Phyllomedusinae, including about 31 species. Although there is some information about the anatomy of these frogs, little is known about the osteology. Here the adult skull of Phyllomedusa sauvagii, both articulated and disarticulated, is described and the intraspecific variation is reported. Additionally, cartilage associated with the adult skull, such as the nasal capsules, auditory apparatus, and hyobranchial apparatus, are included in the analysis. Further examination of disarticulated bones reveals their remarkable complexity, specifically in the sphenethmoid and of the oocipital region. The description of disarticulated bones is useful for the identification of fossil remains as well as providing morphological characteristics that are phylogenetically informative. When comparing the skull morphology with the available information of other species of the genus, Phyllomesusa sauvagii skull resembles more that of P. vaillantii and P. venusta than P. atelopoides. Anat Rec, 299:557-572, 2016. © 2016 Wiley Periodicals, Inc.
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Books by Ricardo Montero
Contiene información sobre las 93 especies más conspicuas de los Vertebrados de la región de Bajo De La Alumbrera (Catamarca, Argentina), incluyendo fotografías, dibujos, su descripción, distribución, biología y estado de conservación.
Nota: hay una tercera edición (2018) más actualizada.
Papers by Ricardo Montero
attached to the cephalic condyle of the quadrate, embedded in the bodenaponeurosis and jaw adductor muscles of Ophiodes intermedius (Anguidae). The other sesamoid is found at the base of the basicranium of several squamates, capping the sphenoccipital tubercle, on the lateral side of the basioccipital–basisphenoid suture. This bone has previously been reported as “element X.” We reinterpret it as a basicranial sesamoid, as it is associated with tendons of the cranio-cervical muscles. This bone seems to have the function of resisting tension-compression forces generated by the muscle during flexion the head. This element was previously known in several squamates, and we
confirmed its presence in three additional squamate families: Gymnophthalmidae, Gekkonidae, and Pygopodidae. The evidence suggests that cranial sesamoids are a widespread character in squamates, and it is possible that this feature has been present since the origin of the group
Contiene información sobre las 93 especies más conspicuas de los Vertebrados de la región de Bajo De La Alumbrera (Catamarca, Argentina), incluyendo fotografías, dibujos, su descripción, distribución, biología y estado de conservación.
Nota: hay una tercera edición (2018) más actualizada.
attached to the cephalic condyle of the quadrate, embedded in the bodenaponeurosis and jaw adductor muscles of Ophiodes intermedius (Anguidae). The other sesamoid is found at the base of the basicranium of several squamates, capping the sphenoccipital tubercle, on the lateral side of the basioccipital–basisphenoid suture. This bone has previously been reported as “element X.” We reinterpret it as a basicranial sesamoid, as it is associated with tendons of the cranio-cervical muscles. This bone seems to have the function of resisting tension-compression forces generated by the muscle during flexion the head. This element was previously known in several squamates, and we
confirmed its presence in three additional squamate families: Gymnophthalmidae, Gekkonidae, and Pygopodidae. The evidence suggests that cranial sesamoids are a widespread character in squamates, and it is possible that this feature has been present since the origin of the group