Ulyses Pardiñas

Consejo Nacional de Ciencia y Tecnología (CONICET)

The caviomorph rodent Abrocoma uspallata Braun, J.K. and Mares, M.A. (2002). Systematics of the Abrocoma cinerea species complex (Rodentia: Abrocomidae), with a description of a new species of Abrocoma . J. Mammal . 83: 1–19, doi: 10.1093/jmammal/83.1.1, stands as the most recently described species within its genus and remains one of the least stu...

The cricetid rodent Abrothrix andina purportedly comprises five taxa, described from specimens collected across three countries, spanning approximately 20 degrees of latitude. This classification, largely based on morphological studies conducted in the early 20th century, has not been reassessed using modern techniques. The preliminary results pre...

Rodents have received substantial attention in the study of olfaction. However, the rhinarium, the naked part of the nose, which plays an important role in chemical, tactile, and thermal perception, has been relatively overlooked. This study presents a comprehensive analysis of the rhinarium morphology and spatially associated structures (i.e., upp...

The limited temporal completeness and taxonomic accuracy of species lists, made available in a traditional manner in scientific publications, has always represented a problem. These lists are invariably limited to a few taxonomic groups and do not represent up-to-date knowledge of all species and classification. In this context, the B Brazilian meg...

Limited vouchered records exist for Cuniculus paca , the second-largest living caviomorph rodent, documenting its southernmost occurrence. Here, we introduce four new recording sites based on skulls probably discarded by local hunters, with three located in Misiones Province and the fourth marking the first supported evidence in the neighboring Cor...

Lagostomus crassus is a chinchillid rodent exclusively based in an isolated cranium exhumed near Cusco, Peru, by Jan Kalinowski. Although controversial from the very beginning, the validity of the species persisted for more than a century included in treatises and analyses of recent extinctions. Here, we support the hypothesis advanced in the 1960s...

This study presents a comprehensive analysis of the rhinarium morphology and associated features in sigmodontine rodents, a highly diverse group within the Cricetidae family. The research encompassed 483 specimens representing 145 species, accounting for 75% of genera in the clade, including all 13 recognized tribes, three incertae sedis genera, an...

The rodent Graomys griseoflavus has a wide geographical distribution in the Arid Diagonal of South America, showing variation in the diploid number (2n = 33–38) caused by three different Robertsonian (Rb) translocations. Two contrasting hypotheses have been proposed to explain the origin and evolution of this polymorphism: (i) unique and sequential...

Ctenomys paramilloensis Roig et al. (1975. Ctenomys paramilloensis, una nueva especie de tucu-tuco de la Sierra de Uspallata, provincia de Mendoza (Rodentia, Octo-dontidae). In: Resúmenes IV Jornada Argentina de Zoología. Corrientes, Argentina), was coined to represent populations for this caviomorph (Hystricomorpha) subterranean rodent inhabiting...

Sanz-Pérez et al. (2024) recently, based on detrital zircon, presented new maximum depositional ages for several sites of the Neogene of central Argentina to constraint the age of the faunas studied with stable isotopes. Unfortunately , the precise provenance of the dated samples is not clear. In this comment, we discuss the absence of key basic in...

Lagostomus crassus is a chinchillid rodent exclusively based of an isolated cranium exhumed near Cusco, Peru, by Jan Kalinowski. Although controversial from the very beginning, the validity of the species persisted during more than a century included in treatises and analyzes of recent extinctions. Here we support the hypothesis advanced in the '60...

Quaternary small mammals are important proxies for paleoenvironmental reconstructions. The Brazilian record, although famous and continuously growing, is hampered by poor chronological control due to the nature of most of the published assemblages. Here, we present a taphonomic analysis and paleoenvironmental reconstruction based on marsupials, b...

Laelaps (Mesostigmata: Laelapidae) es un género de ácaros que incluye especies ampliamente distribuidas, que parasitan una diversa variedad de pequeños roedores de las familias Cricetidae y Muridae. Estudios recientes han descrito nuevas especies asociadas con roedores de la subfamilia Sigmodontinae (Cricetidae), basándose en datos moleculares y mo...

We describe new Upper Miocene mammalian specimens from the Maimara Formation (Late Miocene to Early Pliocene) exposed at Humahuaca Basin (23°–24°S), northwestern Argentina (NWA), and analyse their taxonomy and relevance for our understanding of the initial stages of the Great American Biotic Interchange (GABI). The stratigraphical and geochronologi...

We document the first occurrence of Sigmodontinae (Mammalia, Rodentia, Cricetidae) from the Pliocene of northern South America, from the San Gregorio Formation of northwestern Venezuela. The recovered isolated molars are identified as Oligoryzomys sp. and Zygodontomys sp., two currently widespread sigmodontines in South America. These records const...

Sigmodontines (Rodentia: Cricetidae), the largest living radiation of Neotropical rodents (90 genera, 489 species), show about 10% having specializations related to a semiaquatic habitat. In addition, this mode of life is unequally distributed among the several clades which compose the subfamily, concentrated in the Ichthyomyini and in a few large-...

Fossil vertebrates, especially mammals, of the Neogene–Quaternary of Central Argentina were fundamental to the construction of time and rock-time scales and the knowledge of the biotic evolution of southern South America. The poverty of fossiliferous localities constrained with radiometric and/or paleomagnetic data heavily complicated the correlati...

INTRODUCCION al volumen tematico en homenaje a la trayectoria academica de Eduardo Pedro Tonni

MICROMAMMAL COMMUNITY CHANGES DURING LATE HOLOCENE–ANTROPOCENE IN SOUTHEASTERN BUENOS AIRES PROVINCE (ARGENTINA). The qualitative and quantitative taxonomic composition of the micromammal assemblages (including didelphimorphs, chiropterans, and rodents) derived from trophic activity of strigiform birds is analyzed. The studied samples have been col...

Figuras suplementarias a: Ulyses F. J. Pardiñas y Marcos Cenizo (2023). Cambios en las comunidades de micromamíferos durante el Holoceno Tardío–Antropoceno en el sudeste de la provincia de Buenos Aires (Argentina). Publicación Electrónica de la Asociación Paleontológica Argentina 23(1): 407–476

A preliminary approach to the comparative anatomy of the rhinarium in sigmodontine rodents, the most speciose living subfamily of the Cricetidae was conducted. Studied material covered about 65% of the generic content of the clade representing the 13 tribal groups today recognized plus some incertae sedis genera as well as two murids (Mus and Rattu...

Abstract: The endemic cricetid rodent Rhagomys septentrionalis was previously known only from its type locality in Ecuador. Four new records are reported here, documenting a northward range extension of about 300 km. Obtained evidence include, for the first time, nests and a video of an individual in the wild. Distribution models suggest that R. s...

Ichthyomyini, a morphologically distinctive group of Neotropical cricetid rodents, lacks an integrative study of its systematics and biogeography. Since this tribe is a crucial element of the Sigmodontinae, the most speciose subfamily of the Cricetidae, we conducted a study that includes most of its recognized diversity (five genera and 19 species...

Grasshopper mice of the genus Onychomys, represented by three living species in North America, have a long and controversial taxonomic history. Usually allocated to either the cricetine or neotomine cricetids, they also have been considered to represent a distinct tribe. Since the discovery and description of the extinct grasshopper mouse relative...

Un breve artículo sobre la introducción de restos macrovegetales al contexto arqueológico de la Cueva Epullán Grande (Neuquén), con énfasis en cactáceas.

Comments on the proposed conservation of Holochilus Brandt, 1835, Proechimys J.A. Allen, 1899 and Trinomys Thomas, 19121 (Mammalia, Rodentia) by the designation of H. sciureus Wagner, 1842 as the type species of Holochilus (Case 3121; see BZN 56: 255-261).

Un resumen expandido que da cuenta de la creación de la Colección de Material de Egagrópilas y Afines "Elio Massoia", primera en su tipo en Argentina, hoy día con más de 100 mil ejemplares catalogados.

Occurrence charts of Pleistocene mammals in the Pampean area, eastern Argentina

Estudio preliminar de la arqueofauna del sitio Laguna de Sotelo (partido de Mar Chiquita, provincia de Buenos Aires, Argentina).

This paper summarizes the research carried out in the counties of General La Madrid and Laprida an area in the north of the Buenos Aires plains bordered by two hill ranges (the Llanura Interserrana Bonaerense) covering over 1 million acres. The research activities included surveys which resulted in the placing of 70 sites, and stratigraphical excav...

Resumen de tesis doctoral

MASSOIA, E. y PARDIÑAS, U. F. J. 1988. Análisis de regurgitados de Tyto alba tuidara de Camping Casa Amarilla, partido de Chascomús, provincia de Buenos Aires. Boletín Científico, Asociación para la Protección de la Naturaleza, 13: 22-24, San Miguel.

MASSOIA, E. y PARDIÑAS, U. F. J. 1988. Pequeños mamíferos depredados por Bubo virginianus en Pampa de Nestares, Departamento Pilcaniyeu, Provincia de Río Negro. Boletín Científico, Asociación para la Protección de la Naturaleza, 3: 23-27, San Miguel.

Este es el primer registro holocénico de los cricétidos Bibimys y Pseudoryzomys documentado en la provincia de Buenos Aires, en el sitio arqueológico Cueva Tixi.

La revisión de algunos cricétidos fósiles de la Colección Ameghino, entre los cuales el género Bothriomys resultó ser un sinónimo senior de Graomys, pero se evitó el reemplazo nomenclatorial (que hubiera sido atendible por criterio de prioridad)

Este es el primer planteo formal, con datos paleontológicos, sobre el cambio de las comunidades de pequeños mamíferos en la región pampeana de Argentina producto del interjuego entre eventos climáticos tardíos e impacto antrópico

Presas de Bubo virginianus en Cueva Epullán, Departamento Collón Cura, Provincia de Río Negro -I-. Boletín Científico, Asociación para la Protección de la Naturaleza, 7: 17-27, San Miguel.

Nuevos cráneos de mamíferos fósiles argentinos -2- Paedotherium typicum en la Barranca de Los Lobos, partido de General Pueyrredón, provincia de Buenos Aires y mastofauna asociada. Boletín Científico, Asociación para la Protección de la Naturaleza, 10: 11-15, San Miguel.

Algunos datos sobre la dieta mastofaunística de Tyto alba en Salinas del Bebedero, Departamento La Capital, provincia de San Luis. Boletín Científico, Asociación para la Protección de la Naturaleza, 2: 8-12, San Miguel.

Nota sobre la fauna de pequeños roedores de Valle Hermoso, Departamento Escalante, provincia de Chubut. Boletín Científico, Asociación para la Protección de la Naturaleza, 11: 13-15, San Miguel.

Presas de Bubo virginianus en Cañadón Las Coloradas, Departamento Pilcaniyeu, Provincia de Río Negro. Boletín Científico, Asociación para la Protección de la Naturaleza, 4: 14-19, San Miguel.

Un resumen de una exposición, en las antiguas reuniones anuales de comunicaciones de la Asoc Paleontológica Argentina

Revista Azara (ISSN 2683-7692) 2022 (10):56-62. La costa atlántica bonaerense es un ambiente sumamente dinámico, sujeto a intensas fuerzas naturales que determinan un frágil equilibrio. En ella, no solo confluye el mar y la tierra, sino también una diversidad biológica única junto a un invaluable patrimonio arqueológico y paleontológico, que está s...

The genus Calomys includes several species that have very similar external morphologies, which often leads to confusing field identification and has resulted in conflictive taxonomic histories. One of its clades involves large‐sized body forms, known as the Calomys callosus complex. In a previous study, a biogeographic hypothesis was proposed to ex...

Rhagomys is a genus of South American cricetids composed of three living species. They occur in eastern Andean and lowland tropical forests. Since description of this genus more than a century ago, it was treated as an enigmatic form within Sigmodontinae, varyingly thought to be allied to different suprageneric groups, with several scholars highlig...

The Andean cloud forests of Ecuador are home to several endemic mammals. Members of the Thomasomyini rodents are well represented in the Andes, with Thomasomys being the largest genus (47 species) of the subfamily Sigmodontinae. Within this tribe, however, there are genera that have escaped a taxonomic revision, and Chilomys Thomas, 1897, constitut...

The South American rodent genus Ctenomys is well represented throughout much of southern Patagonia by the polytypic “magellanicus” lineage. In western Argentina, members of this lineage occur from 35 °S to 54 °S latitude. In comparison, the taxonomy of Ctenomys in northeastern Patagonia remains poorly known. This ∼160,000 km² region consists primar...

Aim: Comprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroeco...

Se estudió una pequeña colección de muroideos (Rodentia, Muridae) fósiles provenientes del Miembro Media de la Formación Nuapua (Holoceno inferior) exhumada en la Quebrada de Nuapua (20° 52' S; 63 ° 04' O; 500 m sobre el nivel del mar), departamento Chuquisaca, Bolivia. Se determinaron restos asignables a los sigmodontinos Holochilus chacarius baln...

The diversity of the oryzomyine rat Mindomys (Cricetidae, Sigmodontinae, Oryzomyini), is doubled here with the description of a new species from the remote Cordillera de Kutukú (Ecuador). The novel form can be easily differentiated from Mindomys hammondi-type species of the genus-by a large set of anatomical traits including, among others, larger j...

Cueva Huenul 1 site, located in the extreme north of Neuquén Province, is notable for a paleontological component with extinct megafauna in the Late Pleistocene (~16.6 ka cal BP) and three archaeological components that cover, discontinuously, the Holocene. The site presents small mammals in the four components. Previously, 1426 well-preserved spec...

The monotypic genus Salinomys (Cricetidae, Sigmodontinae) includes tiny mice with specialist adaptations to desert habitats characteristic of Argentinian shrubland. We report on a population of Salinomys delicatus from Central La Pampa Province, Argentina, representing a 450 km southerly extension to its known distribution. Importantly, this stress...

We conducted the first taphonomic and paleoenvironmental study based on late Pleistocene-Holocene small mammal remains recovered from the famous Mylodon Cave (Cerro Benítez area, Última Esperanza, Chile). Most of the analyzed material came from the extensive excavations made by Earl Saxon in 1976. We also studied late Holocene small mammal samples...

In the Andean portion of northern Patagonia, populations of Ctenomys are found from low-elevation plains to high-elevation meadows and valleys. Despite their prevalence, the taxonomy of these subterranean rodents remains poorly resolved. Using genetic and morphological data obtained from museum specimens and animals collected in the field, we exami...

Una breve correspondencia donde, a partir de una identificación taxonómica incorrecta sobre material arqueológico caribeño, se resignifica la posibilidad de introducción de múridos exóticos en épocas pre-hispánicas.

One of the largest members of Sigmodontinae, the extinct Megaoryzomys curioi from Santa Cruz Island in the Galápagos Archipelago (Ecuador), is traditionally treated as a representative of Thomasomyini. We contrasted this hypothesis based on a direct study of craniodental material of M. curioi, including a well-preserved skull assessed through CT-sc...

The monotypic rodent Mindomys Weksler, Percequillo & Voss, 2006 (Cricetidae, Sigmodontinae) is one of the rarest members of the speciose tribe Oryzomyini. As this species is restricted to the Chocó forests of the western Andean slope in northern Ecuador, our knowledge is based on a few specimens collected decades ago. Here we add the first data on...

Most of the contemporary debate about the origin and early diversi cation of sigmodontine rodents, the most diverse living subfamily of cricetids, is based on the analysis of molecular evidence. In order to promote interest and highlight the importance of fossil evidence, we conducted a critical review of the paleontological record for this group o...

Based on various resources, the original collection localities for ve species of rodents whose type specimens were collected by Thomas Bridges during the 19 th century are discussed. The taxa examined are the caviomorph species Aconaemys fuscus and Ctenomys pontifex, and the cricetids Abrothrix hirta, Euneomys mordax, and Paynomys macronyx. A. fusc...

En este preprint presentamos un breve comentario originado a partir de una identificación taxonómica errónea que puede traer luz sobre la cronología del ingreso de los múridos en América. Espero que les resulte interesante y, como siempre es el caso de los preprints, cualquier sugerencia, comentario, corrección será atendido. Muchas gracias.

En este preprint, que nos enorgullece presentar a los colegas (para recibir los comentarios, críticas, adiciones, correcciones que deseen hacernos, a fin de enriquecerlo) distinguimos al enigmático género Rhagomys con una nueva tribu, a la par que ponemos en evidencia sus características únicas en el contexto de los Oryzomyalia. Más aún, proponemos...

Laelaps mazzai is a species with five different morphotypes, each one related to their own rodent host species Non-Cognitive Predictors of Student Success: A Predictive Validity Comparison Between Domestic and International Students INTRO • Laelaps mazzai is a mite with poorly studied morphology and taxonomic status, a few studies have been associa...

The vertebrate fossil record of the Pampean Region of Argentina occupies an important place in South American vertebrate paleontology. An abundance of localities has long been the main basis for constructing the chronostratigraphical/geochronological scale for the late Neogene–Quaternary of South America, as well as for understanding major patterns...

There have been only a very few collections of small mammals in the Misiones Province, Argentina, a fact that is reflected not only in a poor general knowledge of the sigmodontine rodent assemblages but also in their conservation status (i.e., many are characterized as data deficient). In this contribution, which partially follows the style of a “d...

Subterranean rodents Ctenomys are iconic representatives of the mammalian fauna from southern South America. Based on molecular data, eight lineages have been identified within the genus, although species-level identifications and relationships are still debated. Until now, the “ magellanicus ” clade has been the only lineage mentioned from arid, e...

While hypsodonty mostly is associated with medium to large body sizes in sigmodontine rodents, highcrowned molars combined with small bodies rarely are recorded. This latter condition is present in Neomicroxus (Sigmodontinae, incertae sedis), a genus of high-Andean cricetids also characterized by a noticeable set of cranial traits, including enlarg...

We re-evaluate the tribal allocation of Olympicomys vossi, an extinct member of Sigmodontinae (Rodentia, Cricetidae). Originally described from fragmentary jaws, this taxon was considered as a Phyllotini. In light of new remains, including hemimandibles and for the first time an anterior part of the cranium with the upper dentition, we propose that...

Dando continuidad a esta línea que nos hemos planteado de compartir (máxime en estos tiempos tan duros que nos tocan) nuestras investigaciones ni bien son generadas, en forma de pre-print, acá presentamos un estudio donde hemos combinado la descripción de un magnífico nuevo representante de la tribu Oryzomyini de la remota Cordillera de Kutukú, en...

The monotypic genus Salinomys (Cricetidae, Sigmodontinae) includes tiny mice with specialist adaptations to desert habitats characteristic of Argentinian shrubland. We report on a population of Salinomys delicatus from Central La Pampa Province, Argentina, representing a 450 km southerly extension to its known distribution. Importantly, this stress...

We present a topological analysis of the third upper molars (M3) using the recently developed ICAMER nomenclatural system as a way to understand the dental morphological similarity in sigmodontine rodents, the most speciose subfamily of cricetids. The method is explored in Scapteromys aquaticus and Abrothrix olivacea, taxa belonging to two diverse...