- Paleoecology, Vertebrate Paleontology, Dinosaur Paleontology, Pleistocene Vertebrate, Pleistocene Fossils, Vertebrate Fossil Preparation, and 46 moreFossil Microvertebrates, Vertebrate Fossil Conservation, Vertebrate Ichnology, Osteology, Archaeozoology, Zooarchaeology, Paleontology, Morphometry, Paleoichnology, Vertebrate Evolution, Paleobiology, Vertebrate Palaeontology, Life History Evolution, Systematics (Taxonomy), Vertebrate Paleontology of Xenarthra, Paleontologia de Vertebrados, Polaco óscar, Environmental Studies, Mammalian Paleontology, Mammuthus Hayi, Areas Protegidas De Aguascalientes, Zonas Protegidas De Aguascalientes, Patrimonio Natural De Aguascalientes, Paisajes Naturales En Aguascalientes, Fosiles En Aguascalientes, Habitos Alimenticios Del Caballo, Ornithopods, Deinosuchus Riograndensis, Conservacion De Aguascalientes, Areas Naturales Protegidas En Aguascalientes, Ichthyosauria, Biology, Geology, Evolutionary Biology, Earth Sciences, Iguanodontid, Zoology, Evolution, Phylogenetics, Paleoclimatology, Areas Naturales Protegidas De Aguascalientes, Ecology, Stratigraphy, Taphonomy, Palaeontology, and Paleopathologyedit
En este trabajo se analizaron, mediante espectroscopia Raman, muestras fósiles de trilobites, amonita, y restos de huesos largos de équidos, donde estos últimos fueron recolectados en el lago de Chapala. Los espectros Raman fueron medidos... more
En este trabajo se analizaron, mediante espectroscopia Raman, muestras fósiles de trilobites, amonita, y restos de huesos largos de équidos, donde estos últimos fueron recolectados en el lago de Chapala. Los espectros Raman fueron medidos en diferentes zonas de cada muestra a temperatura ambiente al emplear la longitud de onda de excitación de 830 y 785 nm. De los espectros Raman obtenidos se observó que hay variaciones en el proceso de fosilización del interior al exterior de la muestra para los fósiles de amonitas. También, se observaron diferencias para diversas zonas del mismo hueso fósil debido al enraizamiento.
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The Mosasauridae underwent a major radiation early in the Late Cretaceous, with the subfamilies Plioplatecarpini and Tylosaurini appearing in the Turonian. Here we report an almost complete mosasaur skull assigned to the plioplatecarpine... more
The Mosasauridae underwent a major radiation early in the Late Cretaceous, with the subfamilies Plioplatecarpini and Tylosaurini appearing in the Turonian. Here we report an almost complete mosasaur skull assigned to the plioplatecarpine genus Yaguarasaurus. The specimen was discovered southwest of Vallecillo in the northeastern Mexico state of Nuevo Leon, about 80 km north of Monterrey, in a laminated limestone layer of the upper member of the Agua Nueva Formation (Upper Turonian - ?Lower Coniacian). The specimen is referred to as a new species, Y. regiomontanus. This is the first report of Yaguarasaurus from Mexico and the most complete of the Americas. At roughly 5 m in length, it is one of the earliest large mosasaurids. Along with Yaguarasaurus columbianus, Russellosaurus coheni, and an unnamed plioplatecarpine from Texas, it documents the rapid diversification and expansion of plioplatecarpines in the marine realm in the Turonian.
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We report the recovery of the holotype material for the land tortoise Gopherus auffenbergi, reported by Oswaldo Mooser in 1971 from the Pleistocene Cedazo local fauna in Aguascalientes, which had been long lost since the death of Mooser... more
We report the recovery of the holotype material for the land tortoise Gopherus auffenbergi, reported by Oswaldo Mooser in 1971 from the Pleistocene Cedazo local fauna in Aguascalientes, which had been long lost since the death of Mooser in 1983. The recovered material consist in the complete carapace and some postcranial elements.
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We report a new Pleistocene vertebrate fossil locality outcropping near the town of Emilio Carranza, southwest of Zacatecas State, Mexico. The fossil material recovered so far include molars and tusks of the proboscidean Mammuthus,... more
We report a new Pleistocene vertebrate fossil locality outcropping near the town of Emilio Carranza, southwest of Zacatecas State, Mexico. The fossil material recovered so far include molars and tusks of the proboscidean Mammuthus, molariforms of the equid genus Equus as well as postcranial material assigned to both genera.
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Preliminary taxonomic results on a new local faunal assemblage from the Late Miocene assigned to the Hemphillian NALMA that have been collected in the continental facies outcropping near the townships of Tecolotlan and Juchitlan, in the... more
Preliminary taxonomic results on a new local faunal assemblage from the Late Miocene assigned to the Hemphillian NALMA that have been collected in the continental facies outcropping near the townships of Tecolotlan and Juchitlan, in the Mexican State of Jalisco.
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En 1885, el geólogo Mariano Bárcena escribió un comentario acerca de unas "impresiones fisiológicas" en las cercanías de San Juan de los Lagos, Jalisco. En 1894, el naturalista francés Alfredo Dugés, publicó el reporte formal de... more
En 1885, el geólogo Mariano Bárcena escribió un comentario acerca de unas "impresiones fisiológicas" en las cercanías de San Juan de los Lagos, Jalisco. En 1894, el naturalista francés Alfredo Dugés, publicó el reporte formal de dichas impresiones donde registra huellas fósiles de aves y de un felino del Plio-Pleistoceno. Ciento doce años después, el análisis de la paleoicnofauna reportada por Dugés, permitió el redescubrimiento del material ilustrado por él, así como la presencia de material adicional en otras colecciones, similar al descrito por Dugés. El sitio de donde proceden las huellas, se localizó en el municipio de San Juan de los Lagos; las huellas se encuentran conservadas en sedimentos lacustres con influencia volcánica. La diversidad de huellas de vertebrados no sólo se restringe a las identificadas inicialmente; se conoce ahora la existencia de huellas de aves del orden Charadriformes (dos morfotipos relativos a la morfofamilia Avipedidae), huellas de artiodá...
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Oswaldo Mooser (1903-1983) describe lo que considera una asociación faunística unitaria del Pleistoceno medio procedente de la región central de Aguascalientes, denom-inándola "Fauna Cedazo". El estudio posterior de algunos de... more
Oswaldo Mooser (1903-1983) describe lo que considera una asociación faunística unitaria del Pleistoceno medio procedente de la región central de Aguascalientes, denom-inándola "Fauna Cedazo". El estudio posterior de algunos de los materiales colectados por Mooser nos ha permitido cuestionar la contemporaneidad de los taxa reportados, lo cual sugiere que se trata de representantes de diferentes edades que de alguna manera se han mezclado en los depósitos fluviales (arroyos de El Cedazo y San Francisco, principalmente), por ejemplo, la presencia tanto del complejo Mammuthus hayi/meridionalis como de Mam-muthus columbi en la Fauna Cedazo. Aunque posteriormente otros investigadores han reportado hallazgos de mega-fauna pleistocénica en el área, hasta ahora no ha sido posible dilucidar satisfactoriamente esta cuestión. Aunado a esta problemática, debido al crecimiento de la zona urbana de la ciudad de Aguascalientes, la mayoría de las localidades originalmente trabajadas por Mo...
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Research Interests: Paleobiology, Geography, Art, Ichnology, Paleoenvironment, and 13 morePaleoichnology, Vertebrate Palaeontology, Vertebrate Paleontology, Mammalian Paleontology, Mammalian paleoecology, Mexico, Jalisco, Trace Fossils, Fossil Mammals, Novedades Sobre Paleontología, Pleistocene megafauna, Vertebrate Tracks, and MEXICO
New hadrosaurid postcranial material is reported, collected near Presa San Antonio, Parras de la Fuente municipality, Coahuila, Mexico, in a sedimentary sequence belonging to the upper Campanian of the Cerro del Pueblo Formation, in the... more
New hadrosaurid postcranial material is reported, collected near Presa San Antonio, Parras de la Fuente municipality, Coahuila, Mexico, in a sedimentary sequence belonging to the upper Campanian of the Cerro del Pueblo Formation, in the Parras Basin. The skeletal remains include partial elements from the pelvic girdle (left ilium, right pubis, ischium, and incomplete sacrum), a distal end of a left femur, almost complete right and left tibiae, right metatarsals II and IV, cervical and caudal vertebrae. Also, partially complete forelimb elements are present, which are still under preparation. The pubis shows characters of the Lambeosaurinae morphotypes, but the lack of cranial elements does not allow us to directly differentiate this specimen from the already described hadrosaurid taxa from the studied area, such as Velafrons coahuilensis, Latirhinus uitstlani, and Kritosaurus navajovius. This specimen, referred as Lambeosaurinae indet., adds to the fossil record of the hadrosaurids ...
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Here we report new hadrosaur remains recovered from the Cerro del Pueblo Formation (Upper Cretaceous: Campanian) at La Parrita locality, northeastern Mexico. Although the material is fragmentary, the identification of dental microwear in... more
Here we report new hadrosaur remains recovered from the Cerro del Pueblo Formation (Upper Cretaceous: Campanian) at La Parrita locality, northeastern Mexico. Although the material is fragmentary, the identification of dental microwear in three out of the four teeth collected is notable. This sample allows for a preliminary assessment of hadrosaur dental microwear from this geographic region and time frame. The variables studied were the orientation and average count of scratches, average count of pits, and average microwear feature width in an area of 400 X 400 μm at 35X magnification. The results show a predominance of dorsodistally-ventromesially inclined scratches in all three teeth indicating that the mandible primarily moved in an orthopalinal direction during the power stroke. The pattern of scratch orientation we recorded is comparable to that reported for different hadrosaur species from Alberta, Canada, and Wyoming, U.S.A.; suggesting similar jaw mechanics in the hadrosaurs...
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3y una mandibula asociada con ambos I 2 y las series P 3 -M 3 , parte anterior de una mandibula aislada con el I 2 izquierdo y ambas series P 3 -M 3 , una mandibula aislada con la serie P 3 -M 3 pero sin sinfisis, molares superiores... more
3y una mandibula asociada con ambos I 2 y las series P 3 -M 3 , parte anterior de una mandibula aislada con el I 2 izquierdo y ambas series P 3 -M 3 , una mandibula aislada con la serie P 3 -M 3 pero sin sinfisis, molares superiores aislados, dos magno derechos, un metacarpo III izquierdo y la primera falange del digito III derecho. Se observaron variaciones morfologicas en el material examinado que refleja diferencias de edad y/o sexo entre los individuos. Teleoceras hicksi se encuentra en la Cuenca de Tecolotan asociado con Dinohippus mexicanus, Nannippus aztecus, Neohipparion eurystyle, Astrohippus stockii y Borophagus secundus, por lo que la edad de la fauna corresponde al Henfiliano tardio. Palabras clave: Cuenca de Tecolotlan, Jalisco, Rhinocerotidae, Teleoceras hicksi, Henfiliano tardio.
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Research Interests: Geography, Paleontology, Vertebrate Palaeontology, Vertebrate Paleontology, Cretaceous life, and 12 moreDinosaur Paleontology, Mexico, Dinosauria, Dinosaurs, Cretaceous, Late Cretaceous, Mesozoic vertebrates, Mexican Paleontology, Dinosaurs and Mesozoic life, Ankylosaurs, MEXICO, and Mexican Dinosaurs
Sobre descubrimientos paleontologicos realizados hacia finales del siglo XIX de diversos grupos de vertebrados fosiles, principalmente megafauna pleistocenica, con antiguedades que oscilan entre 300,000 y 11,800 anos, en el estado de... more
Sobre descubrimientos paleontologicos realizados hacia finales del siglo XIX de diversos grupos de vertebrados fosiles, principalmente megafauna pleistocenica, con antiguedades que oscilan entre 300,000 y 11,800 anos, en el estado de Puebla que despertaron el interes de importantes paleontologos, geologos y arqueologos como Edward D. Cope, Manuel Villada, Johannes Felix, Hans Lenk, Henry F. Osborn, Wilhelm Freudenberg y Juan Armenta Camacho, entre muchos mas.
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The two study areas are located in the northeast part of the Chihuahua state, Mexico; the first one is called "Región Altares" and the second one is known as "Región San Miguel". The deposits present in the Región... more
The two study areas are located in the northeast part of the Chihuahua state, Mexico; the first one is called "Región Altares" and the second one is known as "Región San Miguel". The deposits present in the Región Altares are exclusively from the continental and marine members of the Late Cretaceous Aguja Formation; the Región San Miguel has some small windows that show badly weathered portions of the Javelina Formation, and also displays outcrops of the continental and marine sections of the Aguja Formation. The age range extends from Late Campa-nian to Late Maastrichtian (83.5-65.5 Ma). The continental member of the Aguja Formation consists of greenish-gray mudstones and yellowish-gray sandstones that present ripple marks in the lower part of the section along with cross stratifi-cation, as well as limonite lenses in smaller propor-tion. The marine member is conformed by a sequence of dark gray mudstones, and yellowish-gray limolites.
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Research Interests: History of Paleontology, History of Science, Vertebrate Palaeontology, Vertebrate Paleontology, Dinosaur Paleontology, and 8 moreDinosaurian Paleontology, Dinosaurs, Dinosaur Tracks, Early Vertebrate Palaeontology, Dinosaur footprints and trackways, History of Vertebrate Paleontology, Mexican Paleontology, and Marginocephalian dinosaurs
Dr. Alfredo Dugés was an eminent French naturalist who lived in Guanajuato, Mexico, in the late XIX and early XX centuries. He is well-known for his studies in Herpetology, Ictiology and Ornitology of Mexico, but he also made very... more
Dr. Alfredo Dugés was an eminent French naturalist who lived in Guanajuato, Mexico, in the late XIX and early XX centuries. He is well-known for his studies in Herpetology, Ictiology and Ornitology of Mexico, but he also made very important contributions to the Mexican Vertebrate Paleontology. Fortunately we have been able to find most of his paleontological collections are still housed in Guanajuato, Mexico; in the School of Mines and in the Museum that bears his name.
Research Interests: Paleontology, History of Science, Vertebrate Palaeontology, Vertebrate Paleontology, Mexico, and 15 moreGuanajuato, Epistemología, Filosofía, Early Vertebrate Palaeontology, Paleontologia de Vertebrados, Política Científica, Geología, Biología, Mexican Paleontology, Historia de la Ciencia, Paleontología, Divulgacion CIentifica, Mamíferos de Guanajuato, MEXICO, and Historia De La Ciencia
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ProQuest uses cookies for authentication and authorization at the beginning of and during your ProQuest session; if cookies are disabled or rejected by your browser or another application, you may see this message, even if you have successfully logged in.
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... E. Díaz-Martínez e I. Rábano (Eds.), 4th European Meeting on the Palaeontology and Stratigraphy of ... the resulting interdigital pad is longer and thus capable of producing a footprint morphology as ... here assumed that the producer... more
... E. Díaz-Martínez e I. Rábano (Eds.), 4th European Meeting on the Palaeontology and Stratigraphy of ... the resulting interdigital pad is longer and thus capable of producing a footprint morphology as ... here assumed that the producer of the San Juan de los Lagos footprints had, as ...
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ABSTRACT Toxodonts were South American rhinoceros-like mammals, belonging to the extinct group Notoungulata. Prior to 2004, the northernmost record of toxodonts was from Guatemala, in Central America (Woodburne, 1969); however, Polaco and... more
ABSTRACT Toxodonts were South American rhinoceros-like mammals, belonging to the extinct group Notoungulata. Prior to 2004, the northernmost record of toxodonts was from Guatemala, in Central America (Woodburne, 1969); however, Polaco and coworkers reported the occurrence of toxodonts in two different localities from Mexico (Polaco et al. 2004). A right mandibular ramus was collected from Hihuitlán, Michoacán, western Mexico, and partial molars and an incomplete upper incisor were collected from la Estribera, Veracruz, eastern Mexico (Polaco et al. 2004). One of the authors (C.O.H.M.) collected fossil material from a Pleistocene locality in the Municipio of Pánuco, northern Veracruz (587592.48 m E, 2442482.10 m N). This material included at least four isolated toxodont molars, the subject of this report (Figure 1). However, the authors were recently informed about the existence of at least four other partial molars collected at the same locality. Two of the molars presented here are a right M 1 and a left M 2 ; the other two specimens are a right P 4 and a left M 1 (Figure 1). These specimens are slightly larger than the specimens reported by Polaco et al. (2004), suggesting a rather mature individual. The right M 1 is 54 mm long (as preserved), 110 mm tall, and 17.5 mm broad (at the level of the entonconid; the left M 2 is 52 mm long, 108 mm tall, and 23 mm broad (at the protoconid-paraconid level); the right P 4 is 131 mm tall, 39 mm at its widest portion of the crown, and 28 mm in anteroposterior breadth; the left M 1 is 114 mm tall (as preserved), 63 mm at its widest portion, and 29 mm in anteroposterior breadth. As noticed by Polaco et al. (2004), all Central American toxodont fossils have been assigned to Mixotoxodon larensis Van Frank (1957), a toxodont first reported from northern Venezuela (Laurito 1993; Lucas et al. 1997; Polaco et al. 2004; Webb and Perrigo 1984). The Mexican fossils show dental features similar to those present in Mixotoxodon larensis; however, there exist some subtle morphological differ-ences, such as the meta-entoconid folds in both right M1 and left M2. How-ever, more material is still needed to know if these features represent only 1 2 3 4 5 7 6 8 12 P R O O F CURRENT RESEARCH IN THE PLEISTOCENE Vol. 28, 2011 30 morphological variation within a single species or if the Mexican toxodont really represents a new taxon. Hulbert (2001) suggested the occurrence of toxodonts in Mexico; Polaco et al. (2004) confirmed their presence. The occurrence of toxodonts in western and eastern México strongly suggests the possibility of finding more toxodont remains in other Pleistocene deposits present in coastal states of the Country, thus favoring the idea of toxodont migration to northern areas of North America. Authors want to thank Dr. Enrique Ortega Lozano, who initiated the fossil collection at the locality.
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The study of the recently collected cranial and post-cranial material from different localities in Northern Mexico has led to confirm the presence of at least one distinct very large chasmosaurine taxa from the Olmos Formation andit has... more
The study of the recently collected cranial and post-cranial material from different localities in Northern Mexico has led to confirm the presence of at least one distinct very large chasmosaurine taxa from the Olmos Formation andit has also revealed the notable absence of centrosaurines in this formation.
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As a result of the fieldwork and recent research in the Olmos Formation (Upper Cretaceous) north of Coahuila, increases the knowledge and understanding of the Campanian-Maastrichtian dinosaurs south of Laramidia This research has... more
As a result of the fieldwork and recent research in the
Olmos Formation (Upper Cretaceous) north of Coahuila, increases the
knowledge and understanding of the Campanian-Maastrichtian dinosaurs south of
Laramidia This research has documented the evidence of the families Hadrosauridae and
Ceratopsidae, and, for the first time, describes the presence of the Nodosauridae family in this
lithostratigraphic unit, in addition to the previous record of the family
Tyrannosauridae
Olmos Formation (Upper Cretaceous) north of Coahuila, increases the
knowledge and understanding of the Campanian-Maastrichtian dinosaurs south of
Laramidia This research has documented the evidence of the families Hadrosauridae and
Ceratopsidae, and, for the first time, describes the presence of the Nodosauridae family in this
lithostratigraphic unit, in addition to the previous record of the family
Tyrannosauridae
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Los ceratópsidos son el grupo más diverso además de ser componentes característicos y abundantes de las asociaciones de dinosaurios del oeste de Norte América (Laramidia) durante el Cretácico Tardío. Estratos del Campaniano han producido... more
Los ceratópsidos son el grupo más diverso además de ser componentes característicos y abundantes de las asociaciones de dinosaurios del oeste de Norte América (Laramidia) durante el Cretácico Tardío. Estratos del Campaniano han producido numerosos especímenes tanto de centrosaurinos como de chasmosaurinos, principalmente de Canadá y Estados Unidos. En contraste, el registro de la parte sur de Laramidia es sorprendentemente escaso. Restos de ceratópsidos son extremadamente raros en el Cretácico Tardío de México, contrastando con las asociaciones más ricas de hadrosaurios. Sin embargo, restos de dinosaurios han sido reportados de estratos mexicanos, aunque la mayoría de este material no es diagnóstico, y solamente dos taxones, Yehuecauhceratops mudei y Coahuilacertops magnacuerna, provenientes de las formaciones Aguja y Cerro del Pueblo (Campaniano) respectivamente, han sido nombrados.
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Here we report new hadrosaur remains recovered from the Cerro del Pueblo Formation (Upper Cretaceous: Campanian) at La Parrita locality, northeastern Mexico. Although the material is fragmentary, the identification of dental microwear in... more
Here we report new hadrosaur remains recovered from the Cerro del Pueblo Formation (Upper Cretaceous: Campanian) at La Parrita locality, northeastern Mexico. Although the material is fragmentary, the identification of dental microwear in three out of the four teeth collected is notable. This sample allows for a preliminary assessment of hadrosaur dental microwear from this geographic region and time frame. The variables studied were the orientation and average count of scratches, average count of pits, and average microwear feature width in an area of 400 X 400 µm at 35X magnification. The results show a predominance of dorsodistally-ventromesially inclined scratches in all three teeth indicating that the mandible primarily moved in an orthopalinal direction during the power stroke. The pattern of scratch orientation we recorded is comparable to that reported for different hadrosaur species from Alberta, Canada, and Wyoming, U.S.A.; suggesting similar jaw mechanics in the hadrosaurs from Coahuila. In contrast, there are significant differences in the average number of pits and microwear feature width between the Alberta and the Coahuila hadrosaurs samples, with the latter presenting more pits and finer microwear features. Given the similar jaw mechanics between the Alberta and Coahuila hadrosaurs, suggested by our analysis, the difference in average number of pits and microwear feature width is probably due to differences in diet and/or the type and amount of grit ingested during feeding. The greater number of pits in the hadrosaurs from Coahuila might indicate that these individuals ingested a greater proportion of hard food items than the Alberta hadrosaurs. Resumen Aquí reportamos nuevos restos de hadrosaurio recuperados de la Formación Cerro del Pueblo (Cretácico Superior: Campaniano) provenientes de la localidad de La Parrita, noreste de México. A pesar de que el material es fragmentario, la identificación de microdesgaste dental en tres de los cuatro dientes recolectados es notable. Esta muestra permite una evaluación preliminar del microdesgaste dental en hadrosaurios de esta región geográfica y durante este marco de tiempo. Las variables estudiadas fueron la orientación y el número promedio de rayones, el número promedio de fosas y el ancho promedio de los rasgos de microdesgaste en un área de 400 X 400 µm con un aumento de 35X. Los resultados muestran que la mayoria de los rayones estan inclinados dorsodistal-ventromesialmente en los tres dientes, lo que indica que la mandíbula se movió principalmente en dirección ortopalinal durante el golpe masticatorio. El patrón de orientación de los rayones que registramos es comparable al reportado para diferentes especies Paleontología Mexicana Volumen 8, núm. 1
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Here we report new hadrosaur remains recovered from the Cerro del Pueblo Formation (Upper Cretaceous: Campanian) at La Parrita locality, northeastern Mexico. Although the material is fragmentary, the identification of dental microwear in... more
Here we report new hadrosaur remains recovered from the Cerro del Pueblo Formation (Upper Cretaceous: Campanian) at La Parrita
locality, northeastern Mexico. Although the material is fragmentary, the identification of dental microwear in three out of the four teeth
collected is notable. This sample allows for a preliminary assessment of hadrosaur dental microwear from this geographic region and
time frame. The variables studied were the orientation and average count of scratches, average count of pits, and average microwear
feature width in an area of 400 X 400 μm at 35X magnification. The results show a predominance of dorsodistally-ventromesially
inclined scratches in all three teeth indicating that the mandible primarily moved in an orthopalinal direction during the power stroke.
The pattern of scratch orientation we recorded is comparable to that reported for different hadrosaur species from Alberta, Canada,
and Wyoming, U.S.A.; suggesting similar jaw mechanics in the hadrosaurs from Coahuila. In contrast, there are significant differences
in the average number of pits and microwear feature width between the Alberta and the Coahuila hadrosaurs samples, with the latter
presenting more pits and finer microwear features. Given the similar jaw mechanics between the Alberta and Coahuila hadrosaurs,
suggested by our analysis, the difference in average number of pits and microwear feature width is probably due to differences in diet
and/or the type and amount of grit ingested during feeding. The greater number of pits in the hadrosaurs from Coahuila might indicate
that these individuals ingested a greater proportion of hard food items than the Alberta hadrosaurs.
locality, northeastern Mexico. Although the material is fragmentary, the identification of dental microwear in three out of the four teeth
collected is notable. This sample allows for a preliminary assessment of hadrosaur dental microwear from this geographic region and
time frame. The variables studied were the orientation and average count of scratches, average count of pits, and average microwear
feature width in an area of 400 X 400 μm at 35X magnification. The results show a predominance of dorsodistally-ventromesially
inclined scratches in all three teeth indicating that the mandible primarily moved in an orthopalinal direction during the power stroke.
The pattern of scratch orientation we recorded is comparable to that reported for different hadrosaur species from Alberta, Canada,
and Wyoming, U.S.A.; suggesting similar jaw mechanics in the hadrosaurs from Coahuila. In contrast, there are significant differences
in the average number of pits and microwear feature width between the Alberta and the Coahuila hadrosaurs samples, with the latter
presenting more pits and finer microwear features. Given the similar jaw mechanics between the Alberta and Coahuila hadrosaurs,
suggested by our analysis, the difference in average number of pits and microwear feature width is probably due to differences in diet
and/or the type and amount of grit ingested during feeding. The greater number of pits in the hadrosaurs from Coahuila might indicate
that these individuals ingested a greater proportion of hard food items than the Alberta hadrosaurs.
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Es descubrimiento del
Acantholipan gonzalezi,
un nodosaurio nuevo
en género y especie en
el sur de lo que fuera el
continente de Laramidia,
apunta a un alto grado
de endemismo entre
los dinosaurios de esta
región de Coahuila en
México.
Acantholipan gonzalezi,
un nodosaurio nuevo
en género y especie en
el sur de lo que fuera el
continente de Laramidia,
apunta a un alto grado
de endemismo entre
los dinosaurios de esta
región de Coahuila en
México.
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Isolated bones and osteoderms of ankylosaurian dinosaurs recovered from Late Cretaceous sediments of northern Coahuila, northeastern Mexico, have been identified as remains of nodosaurids. Here, we summarize these discoveries and provide... more
Isolated bones and osteoderms of ankylosaurian dinosaurs recovered from Late Cretaceous sediments of northern Coahuila, northeastern Mexico, have been identified as remains of nodosaurids. Here, we summarize these discoveries and provide a review on Mexican Ankylosauria from a taxonomic perspective. We also present a new taxon, Acantholipan gonzalezi gen. et sp. nov. from the Pen Formation and provide a phylogenetic analysis integrating the new taxon. A. gonzalezi is the first named ankylosaur from Mexico that adds to the currently rare nodosaurid diversity from southern Laramidia.
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During the past decade, three new endemic taxa of ceratopsian ornithischians have been described from Mexico. Apparently, this group experienced a regional diversification in this area. To date Mexican Ceratopsia are represented by three... more
During the past decade, three new endemic taxa of ceratopsian ornithischians have been described from Mexico. Apparently, this group experienced a regional diversification in this area. To date Mexican Ceratopsia are represented by three species, one of which is a centrosaurine and two are chasmosaurines. Here we provide a critical review on Mexican ceratopsians and formally name a new centrosaurine ceratopsid species from the Aguja Formation as Yehuecauhceratops mudei. We also discuss possible causes for the rapid endemic diversification of Mexican ceratopsians.
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"Se describe el material de Teleoceras hicksi (Perissodactyla, Rhinocerotidae), depositado en el Museo de Paleontología de Guadalajara y en el Museo Regional de Guadalajara, proveniente de los sedimentos fluviolacustres de la Cuenca de... more
"Se describe el material de Teleoceras hicksi (Perissodactyla, Rhinocerotidae), depositado en el Museo de Paleontología de Guadalajara y en el Museo Regional de Guadalajara, proveniente de los sedimentos fluviolacustres de la Cuenca de Tecolotlán, Jalisco, México. Los restos examinados consisten en un cráneo incompleto con las series P2-M3 y una mandíbula asociada con ambos I2 y las series P3-M3, parte anterior de una mandíbula aislada con el I2 izquierdo y ambas series P3-M3, una mandíbula aislada con la serie P3-M3 pero sin sínfisis, molares superiores aislados, dos magno derechos, un metacarpo III izquierdo y la primera falange del digito III derecho. Se observaron variaciones morfológicas en el material examinado que refleja diferencias de edad y/o sexo entre los individuos. Teleoceras hicksi se encuentra en la Cuenca de Tecolotán asociado con Dinohippus mexicanus, Nannippus aztecus, Neohipparion eurystyle, Astrohippus stockii y Borophagus secundus, por lo que la edad de la fauna corresponde al Henfiliano tardío.
Remains of Teleoceras hicksi (Perissodactyla, Rhinocerotidae), housed at the “Museo de Paleontologia” in Guadalajara and the “Museo Regional de Guadalajara”, were recovered from the fluvial lacustrine sediments in the Tecolotlan Basin are described. The studied material includes a partial skull bearing P2-M3 and one lower jaw preserving I2 and P3-M3, the anterior part of an isolated lower jaw with left I2 and P3-M3, one isolated lower jaw with P3-M3 dental series in wish the symphyseal region is missing, also isolated molars, two magnus, one left metacarpus III, and one first phalange of the right digit III. Morphological differences were observed in the material examined attributed to differences in age and/or sex of the individuals. Teleoceras hicksi was found associated with Dinohippus mexicanus, Nannippus aztecus, Neohipparion eurystyle, Astrohippus stockii y Borophagus secundus, suggesting a late Hemphillian age for the faunal association."
Remains of Teleoceras hicksi (Perissodactyla, Rhinocerotidae), housed at the “Museo de Paleontologia” in Guadalajara and the “Museo Regional de Guadalajara”, were recovered from the fluvial lacustrine sediments in the Tecolotlan Basin are described. The studied material includes a partial skull bearing P2-M3 and one lower jaw preserving I2 and P3-M3, the anterior part of an isolated lower jaw with left I2 and P3-M3, one isolated lower jaw with P3-M3 dental series in wish the symphyseal region is missing, also isolated molars, two magnus, one left metacarpus III, and one first phalange of the right digit III. Morphological differences were observed in the material examined attributed to differences in age and/or sex of the individuals. Teleoceras hicksi was found associated with Dinohippus mexicanus, Nannippus aztecus, Neohipparion eurystyle, Astrohippus stockii y Borophagus secundus, suggesting a late Hemphillian age for the faunal association."
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Las primeras excavaciones importantes de animales extintos en territorio poblano se encuentran en las crónicas de los misioneros españoles, pero es hacia finales del siglo XIX cuando el descubrimiento de diversos grupos de vertebrados... more
Las primeras excavaciones importantes de animales extintos
en territorio poblano se encuentran en las crónicas de los misioneros españoles, pero es hacia finales del siglo XIX cuando
el descubrimiento de diversos grupos de vertebrados fósiles,
principalmente megafauna pleistocénica, animales con un peso
superior a 45 kg con antigüedades que oscilan entre 300,000 y
11,800 años, cobra especial importancia. Pronto, los restos de
megafauna encontrados en el estado de Puebla despertaron el
interés de importantes paleontólogos, geólogos y arqueólogos
como Edward D. Cope, Manuel Villada, Johannes Félix, Hans
Lenk, Henry F. Osborn, Wilhelm Freudenberg, Juan Armenta Camacho, Harold Malde, Cynthia Irwin-Williams, Virginia S. McIntyre y Ekke Guenther, entre otros. Muchos de los trabajos se centraron en Valsequillo, una de las zonas con restos de megafauna más importantes no sólo en Puebla, sino en todo México
en territorio poblano se encuentran en las crónicas de los misioneros españoles, pero es hacia finales del siglo XIX cuando
el descubrimiento de diversos grupos de vertebrados fósiles,
principalmente megafauna pleistocénica, animales con un peso
superior a 45 kg con antigüedades que oscilan entre 300,000 y
11,800 años, cobra especial importancia. Pronto, los restos de
megafauna encontrados en el estado de Puebla despertaron el
interés de importantes paleontólogos, geólogos y arqueólogos
como Edward D. Cope, Manuel Villada, Johannes Félix, Hans
Lenk, Henry F. Osborn, Wilhelm Freudenberg, Juan Armenta Camacho, Harold Malde, Cynthia Irwin-Williams, Virginia S. McIntyre y Ekke Guenther, entre otros. Muchos de los trabajos se centraron en Valsequillo, una de las zonas con restos de megafauna más importantes no sólo en Puebla, sino en todo México
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Research Interests: History of Paleontology, History of Science, Vertebrate Palaeontology, Vertebrate Paleontology, Dinosaur Paleontology, and 8 moreDinosaurian Paleontology, Dinosaurs, Dinosaur Tracks, Early Vertebrate Palaeontology, Dinosaur footprints and trackways, History of Vertebrate Paleontology, Mexican Paleontology, and Marginocephalian dinosaurs
Research Interests: Paleontology, History of Science, Vertebrate Palaeontology, Vertebrate Paleontology, Mexico, and 13 moreGuanajuato, Epistemología, Filosofía, Early Vertebrate Palaeontology, Paleontologia de Vertebrados, Política Científica, Geología, Biología, Mexican Paleontology, Historia de la Ciencia, Paleontología, Divulgacion CIentifica, and Mamíferos de Guanajuato
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We report a new Pleistocene vertebrate fossil locality outcropping near the town of Emilio Carranza, southwest of Zacatecas State, Mexico. The fossil material recovered so far include molars and tusks of the proboscidean Mammuthus,... more
We report a new Pleistocene vertebrate fossil locality outcropping near the town of Emilio Carranza, southwest of Zacatecas State, Mexico. The fossil material recovered so far include molars and tusks of the proboscidean Mammuthus, molariforms of the equid genus Equus as well as postcranial material assigned to both genera.
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Preliminary taxonomic results on a new local faunal assemblage from the Late Miocene assigned to the Hemphillian NALMA that have been collected in the continental facies outcropping near the townships of Tecolotlan and Juchitlan, in the... more
Preliminary taxonomic results on a new local faunal assemblage from the Late Miocene assigned to the Hemphillian NALMA that have been collected in the continental facies outcropping near the townships of Tecolotlan and Juchitlan, in the Mexican State of Jalisco
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We report the recovery of the holotype material for the land tortoise Gopherus auffenbergi, reported by Oswaldo Mooser in 1971 from the Pleistocene Cedazo local fauna in Aguascalientes, which had been long lost since the death of Mooser... more
We report the recovery of the holotype material for the land tortoise Gopherus auffenbergi, reported by Oswaldo Mooser in 1971 from the Pleistocene Cedazo local fauna in Aguascalientes, which had been long lost since the death of Mooser in 1983. The recovered material consist in the complete carapace and some postcranial elements.
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Esta obra integra gran parte del conocimiento actual de los mamíferos que habitaron el estado de Puebla, principalmente aquellos de edad pleistocena tardía (120 000 a 11 000 años antes del presente) que se hallaron en el área de... more
Esta obra integra gran parte del conocimiento actual de los mamíferos que habitaron el estado de Puebla, principalmente aquellos de edad pleistocena tardía (120 000 a 11 000 años antes del presente) que se hallaron en el área de Valsequillo, al sureste de la capital del estado. Su estudio se inició desde hace más de 100 años y en el mismo han participado aficionados e investigadores nacionales y extranjeros. Además de que los editores tratan de integrar dicha información, a su vez dan a conocer algunos nuevos datos y, sobre todo, un registro fotodocumental muy valioso que ha sido puesto a su disposición, lo que le da un aspecto importante a la obra. Esta compilación representa la base del conocimiento actual de la mastofauna pleistocena poblana y deberá servir como punto de partida para los proyectos y estudios futuros.
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Resumen El trabajo de Alfredo Dugès relacionado con el estudio del registro fósil representa un importante ejemplo del estado de la Paleontología como ciencia durante la segunda mitad del siglo xix. La información que se encuentra en los... more
Resumen El trabajo de Alfredo Dugès relacionado con el estudio del registro fósil representa un importante ejemplo del estado de la Paleontología como ciencia durante la segunda mitad del siglo xix. La información que se encuentra en los dos textos que escribió so-bre Zoología refleja su visión de la importancia del registro fósil como complemento en el estudio de aspectos muy diversos de la biología de los animales y como herramien-ta que permite conocer su historia a través del tiempo geológico. Los cuatro artículos en que describe registros fósiles del Altiplano de México son referencias obligadas para estudiosos de vertebrados del Plioceno y Pleistoceno de México y son trabajos que de-muestran la gran formación de naturalista que Dugès adquirió en un ambiente inte-lectual cosmopolita, caracterizado por importantes descubrimientos y el desarrollo de grandes ideas y teorías sobre la naturaleza. Résumé Les travaux de Alfredo Dugès liés à l'étude du registre fossile, représentent un exemple important de l'état de la paléontologie comme une science au cours de la seconde moitié du xixe siècle. L'information contenue dans les deux textes de zoologie qu'il a écrit reflète ses vues sur l'importance du registre fossile comme un complément des études de très nombreux aspects de la biologie des animaux et aussi comme un outil qui permet de connaitre l'histoire à travers du temps géologique. Les quatre publications décrivant le registre fossile du Plateau Mexicain sont références obligées pour les chercheurs de vertébrés du Pliocène et Pléistocène du Mexique, et sont des oeuvres qui représentent la grande formation de naturaliste que Dugès a acquis dans un envi-ronnement intellectuel cosmopolite, caractérisé par d'importantes découvertes et le développement de grandes idées et théories sur la nature. Abstract Alfredo Dugès' work on the fossil record is an important indicator of the state of the Paleontology as a science during the second half of the nineteenth century. The two
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Alfredo Dugès’ work on the fossil record is an important indicator of the state of the Paleontology as a science during the second half of the nineteenth century. The two books on zoology written by Dugès reflect his view on the... more
Alfredo Dugès’ work on the fossil record is an important indicator of the state of the Paleontology as a science during the second half of the nineteenth century. The two books on zoology written by Dugès reflect his view on the importance of the fossil record as complementary to the study of several aspects of the biology of animals and as a tool that makes it possible to understand their history over geological time. The four scientific articles in which Dugès described fossils from the Mexican Altiplano are essential references for anyone studying the Pliocene and Pleistocene vertebrates of Mexico. Those publications also allow us to infer that Dugès was a naturalist with solid academic training acquired in an exceptional intellectual and cosmopolitan environment; one that was characterized by great scientific discoveries and the development of relevant ideas and theories about nature.
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The discovery of mammoth remains in the Calabacillas ravine, near the capital city of Zacatecas state, in North-Central Mexico brought the attention of the community and we wanted to create an attractive visual comic-like book to... more
The discovery of mammoth remains in the Calabacillas ravine, near the capital city of Zacatecas state, in North-Central Mexico brought the attention of the community and we wanted to create an attractive visual comic-like book to communicate the story of the Pleistocene megafauna that lived in this region and especially of the mammoth who is the main character of the story.
It was publishec by the Centro de Vinculación para el Desarrollo Sustentable (CEVDSU A.C.) with the support of the program Coinversión Social 2010 of the Instituto Nacional de Desarrollo Social, Mexico.
It was publishec by the Centro de Vinculación para el Desarrollo Sustentable (CEVDSU A.C.) with the support of the program Coinversión Social 2010 of the Instituto Nacional de Desarrollo Social, Mexico.
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El yacimiento en San Lucas es de fácil acceso. El camino pasa prácticamente por los diez planchones donde se ha identificado una impresionante cantidad de huellas de dinosaurio. Esto las vuelve un blanco fácil del vandalismo y las expone... more
El yacimiento en San Lucas es de fácil acceso. El camino pasa prácticamente por los diez planchones donde se ha identificado una impresionante cantidad de huellas de dinosaurio. Esto las vuelve un blanco fácil del vandalismo y las expone al deterioro natural.
Los primeros reportes de huellas de dinosaurio corresponden a operarios de la empresa a cargo de la apertura del camino que actualmente pasa por la parte media occidental del Sinclinal de Chaupi Cocha, cuya dimensión es de aproximadamente 10 kilómetros.
Los primeros reportes de huellas de dinosaurio corresponden a operarios de la empresa a cargo de la apertura del camino que actualmente pasa por la parte media occidental del Sinclinal de Chaupi Cocha, cuya dimensión es de aproximadamente 10 kilómetros.
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La histología ósea concede una visión sustancial del crecimiento y biología de los vertebrados fósiles. Muchos de los mayores clados de dinosaurios no avianos han sido extensivamente muestreados para datos de osteología ósea permitiendo... more
La histología ósea concede una visión sustancial del crecimiento y biología de los vertebrados fósiles. Muchos de los mayores clados de dinosaurios no avianos han sido extensivamente muestreados para datos de osteología ósea permitiendo la reconstrucción de su crecimiento así como una evaluación de la evolución de sus cambios de crecimiento a lo largo de su filogenia.