Keyword: Mammalia

Sistemática de mamíferos de Argentina: patrones, tendencias y perspectivas en la acumulación de conocimientos

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La fauna de mamíferos de Argentina incluye 411 especies nativas vivientes y extintas en tiempos históricos (repartidas en 186 géneros, 47 familias y 12 órdenes), además de 21 especies introducidas y asilvestradas. En esta contribución se presenta un análisis de las tendencias históricas y recientes en el conocimiento sistemático de los mamíferos de Argentina y de algunos aspectos geográficos de este proceso. En líneas generales, las curvas de acumulación de nuevas especies son similares a las registradas para los mamíferos neotropicales en su conjunto. El trabajo taxonómico fue inicialmente realizado por investigadores del hemisferio norte, pero en la actualidad es principalmente realizado por científicos latinoamericanos. En los últimos 40 años se describieron 39 especies cuya distribución incluye a la Argentina, casi a razón de una por año. Treinta y una de estas especies nuevas son endémicas de Argentina y tienen distribuciones relativamente restringidas. Las ecorregiones donde se registraron más especies nuevas corresponden a las Yungas Australes, el Monte (Alto y Bajo) y el Chaco Seco, en el centro-oeste, centro y noroeste de Argentina; paradójicamente, algunas de estas ecorregiones se encuentran entre las menos exploradas de nuestro país. Finalmente, por su centralidad en el trabajo taxonómico, se discuten algunos aspectos relacionados con las colecciones de mamíferos en instituciones nacionales.

Systematics of mammals in Argentina: patterns, trends and perspectives in the accumulation of knowledge. The mammalian fauna of Argentina includes 411 living and recently extinct native species (divided into 186 genera, 47 families and 12 orders), as well as 21 introduced and feral species. This contribution presents an analysis of the historical and recent trends in the systematic knowledge of the mammals of Argentina and some geographical aspects of this process. Overall, the accumulation curves for new species are similar to those recorded for neotropical mammals as a whole. The taxonomic work was initially carried out by researchers from the northern hemisphere, but at present it is mainly carried out by Latin American scientists. In the last 40 years, 39 species were described whose distribution includes Argentina, almost at the rate of one per year. Thirty-one of these new species are endemic to Argentina and have relatively restricted distributions. The ecoregions where more new species are registered correspond to the Austral Yungas, the Monte (High and Low) and the Dry Chaco, in west-central, central and northwestern Argentina; paradoxically, some of these ecoregions are among the least explored in our country. Finally, due to its centrality in taxonomic work, some issues related to the national mammal collections are discussed.

On the distinction and availability of the new taxa proposed by Agnolin et al. 2019

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Recently, Agnolin et al. (2019) described 14 new species of mammals, including 12 rodents, one bat, and one carnivore, and one new subspecies of rodent. In addition, these authors proposed several other nomenclatorial acts: some nominal forms were removed from synonymies and hypothesized as distinct species, at the time that three new genera, one subtribe, and one tribe of mammals were also named. We reviewed the merits of all nomenclatorial acts proposed by Agnolin at al. (2019) and concluded that all 14 new species and the new subspecies, as well as those forms removed from synonymies, should be treated as synonyms of already known species. We suggest the same regarding the three new supraspecific taxa presented by Agnolin et al., two of which are not available as they fail to comply with the provisions of the International Code of Zoological Nomenclature. We end this contribution criticizing the way that mammal taxonomy was approached by Agnolin et al. (2019).

Sobre la distinción y disponibilidad de los nuevos taxones propuestos por Agnolin et al. 2019. Recientemente, Agnolin et al. (2019) describieron 14 especies nuevas de mamíferos, incluyendo 12 roedores, un murciélago y un carnívoro, y una nueva subespecie de roedor. Además, estos autores propusieron varios otros actos nomenclatoriales: algunas formas nominales se eliminaron de las sinonimias y se hipotetizaron como especies distintas; se nombraron tres nuevos géneros, una subtribu y una tribu de mamíferos. Revisamos todos los actos nomenclatoriales propuestos por Agnolin et al. (2019) y concluimos que las 14 nuevas especies y la nueva subespecie, así como las formas eliminadas de las sinonimias, deben tratarse como sinónimos de especies ya conocidas. Sugerimos lo mismo con respecto a los tres nuevos taxones supraespecíficos presentados por Agnolin et al. (2019), de los cuales dos no están disponibles ya que no cumplen con las disposiciones del Código Internacional de Nomenclatura Zoológica. Terminamos esta contribución criticando la forma en que Agnolin et al. (2019) realizaron su abordaje taxonómico.

On drivers of Neotropical mammal diversification

The extraordinary diversity of Neotropical biotas needs explanation, and this overview purports to frame extrinsic factors involved in the diversification of Neotropical mammals. The immensity of this topic prompted a rather stark, conceptual approach. I first consider the various environmental and intrinsic factors involved in evolutionary divergence, then the prominent and influential roles of both dispersal and vicariance in biogeographic explanations, and then identify ecological opportunity as a potent but elusive underlying driver. I end the perspective with a series of questions focused on organisms and their landscapes that will likely engage me and other evolutionary biologists for the foreseeable future.

Sobre factores de diversificación de mamíferos neotropicales. La extraordinaria diversidad de biotas neotropicales requiere una explicación, y esta revisión general procura identificar factores extrínsecos involucrados en la diversificación de mamíferos neotropicales. La inmensidad de este tema motivó un enfoque más bien rígido, conceptual. Primero, considero los diversos factores ambientales e intrínsecos involucrados en la divergencia evolutiva, y luego los papeles prominentes e influyentes, tanto de las explicaciones basadas en la dispersión como de las basadas en la vicarianza, para finalmente invocar el papel de la oportunidad ecológica como un factor potente pero elusivo. Termino la perspectiva con una serie de preguntas focalizadas en los organismos y sus paisajes que ocuparán, tanto a mí como a otros biólogos evolutivos, en un futuro próximo.

Sobre fatores de diversificação de mamíferos neotropicais. A extraordinária diversidade de biotas neotropicais precisa de explicação, e esta revisão geral pretende enquadrar fatores extrínsecos envolvidos na diversificação dos mamíferos neotropicais. A imensidão do tema requer uma abordagem marcadamente conceitual. Eu irei considerar em primeiro lugar os diferentes factores ambientais e intrínsecos envolvidos na divergência evolutiva, para em seguida, os papéis proeminentes e influentes de ambos a dispersão e a vicariancia nas explicações biogeográficas, e, em seguida, identificar oportunidades ecológicas como um fator subjacente potente mas elusivo. Eu termino com uma série de perguntas focadas nos organismos e suas paisagens que provavelmente vai me envolver e outros biólogos evolucionistas em um futuro próximo.

Mammals of Mato Grosso, Brazil: annotated species list and historical review

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The state of Mato Grosso is one of the largest (903,357 km²) and most diverse in terms of vegetation in Brazil, encompassing three distinct Neotropical biomes—the Amazon, Cerrado, and Pantanal—therefore holding high faunal diversity. Our goal in this paper was to review the history of mammalogy in this state, and to provide a checklist of mammals, with comments on taxonomy, distribution, conservation status and type of records for the species present in Mato Grosso. These records were based primarily on voucher specimens housed in scientific collections, but a few were based on personal observations and photographs. We listed 268 species belonging to 149 genera, 36 families and 10 orders, which represent 38% of mammal species occurring in Brazil. The most representative families were Phyllostomidae (63 species), Cricetidae (42) and Didelphidae (31). Our list includes 33 threatened species, representing 12% of Mato Grosso mammal species and 30% of all threatened mammal species of Brazil. We discuss the main threats to this group, and argue that social and political projects together with basic scientific knowledge are urgent to ensure a profound change in the current scenario.

Mamíferos de Mato Grosso, Brasil: lista anotada e revisão histórica. O estado de Mato Grosso é um dos maiores (903 357 km²) e mais diversos do país em termos de fitofisionomias, abrangendo três biomas Neotropicais distintos —Amazônia, Cerrado e Pantanal— apresentando, consequentemente, uma elevada diversidade faunística. Os objetivos do presente estudo foram revisar a história da Mastozoologia neste estado e fornecer uma lista atual de mamíferos com comentários a respeito da taxonomia, distribuição, estado de conservação e tipos de registro para as espécies que ocorrem no Mato Grosso. Os registros aqui obtidos basearam-se, primordialmente, em espécimes-testemunho depositados em coleções científicas, mas algumas espécies foram registradas por observações pessoais e fotografias. Foram registradas 268 espécies pertencentes a 149 gêneros, 36 famílias e 10 ordens, o que representa 38% das espécies de mamíferos do Brasil. As famílias mais representativas foram Phyllostomidae (63 espécies), Cricetidae (42) e Didelphidae (31). Nossa lista inclui 33 espécies ameaçadas, representando 12% das espécies de mamíferos do Mato Grosso e 30% das espécies de mamíferos ameaçados do Brasil. Discutimos as principais ameaças associadas a este grupo e apontamos a importância de projetos sociais e políticos, aliados ao conhecimento científico básico, em promover uma mudança profunda nesse cenário atual.

Lista revisada de los mamíferos de Argentina

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Se presenta una lista revisada de los mamíferos de Argentina, incorporando los cambios taxonómicos recientes y los nuevos registros para el país producidos desde la publicación de un listado previo en 2006. Se registraron 409 especies nativas, correspondientes a 181 géneros, 46 familias y 12 órdenes, más 23 especies introducidas con poblaciones silvestres.

Revised checklist of mammals from Argentina. We present a revised checklist of the mammals of Argentina, incorporating recent taxonomical changes and new records of mammals for the country produced since the publication of a previous list in 2006. We recorded 409 native species, corresponding to 181 genera, 46 families and 12 orders, plus 23 introduced taxa with wild populations.

Differences in the mammalian habitat use in a mosaic of vegetation types of an Atlantic rain-forest reserve, Brazil

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This study aimed to evaluate how habitat use by medium and large sized mammals was related to different vegetation types in an Atlantic rain-forest reserve in south-eastern Brazil. Our hypotheses were that each vegetation type found in the Vale Natural Reserve (VNR) will present a different mammal species composition, and that mammal species richness and relative abundance will be higher in areas nearest to water. We installed 39 camera traps in the VNR, and used two covariates to characterize the different vegetation types (density of trees and lianas). We also used one spatial covariate: the distance to the nearest water resource. We recorded 26 medium- and large-sized mammal species. The mammalian assemblage was structured by vegetation type and the proximity of water. The results presented here show that even in a single reserve such as VNR there is a difference in the assemblage composition of medium- and large-sized mammals. Our results also indicate the relevance of water availability when designing protected areas to ensure habitat quality for mammal species. The VNR is one of the major remaining portions of the coastal plain forest of the Atlantic rain forest, and also one of the largest contiguous blocks of this biome.

Diferenças no uso do habitat por mamíferos em um mosaiaco de fitofisionomias em uma reserva de Mata Atlântica, Brasil. O objetivo desse estudo foi verificar como o uso do habitat por espécies de mamíferos de médio e grande porte estava relacionada com as diferentes fitosionomias em uma área protegida de Mata Atlântica, Sudeste do Brasil. Nossas hipóteses foram: cada fitofisionomia encontrada na Reserva Natural Vale (RNV) apresentaria diferentes composições de espécies de mamíferos, e que a riqueza e abundancia relativa das espécies seria maior em áreas próximas dos recursos hídricos. Nós instalamos 39 armadilhas fotográficas na RNV, e utilizamos duas covariadas para caracterizar as diferentes fitofisionomias (i.e. densidade de árvores e de lianas). Nós também utilizamos uma covariada espacial: a distância do recurso hídrico mais próximo. Nós registramos 26 espécies de mamíferos de médio e grande porte. A comunidade de mamíferos foi estruturada pelos diferentes tipos de fitofisionomias e pela proximidade da água. Os resultados apresentados aqui mostra que mesmo em uma única reserva é, como a RNV, existe uma diferença na composição de mamíferos de médio e grande porte. Além disso, nossos resultados também destacam a relevância da água na determinação de uma área protegida para garantir a qualidade do habitat para as espécies de mamíferos. A RNV faz parte de um dos maiores blocos de Mata de Tabuleiro da Mata Atlântica, e também representam um dos maiores remanescentes do bioma.

Mammals of the Cosigüina Peninsula of Nicaragua

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Nicaragua’s Cosigüina Peninsula, located at the northwestern tip of the country, is one of the most poorly studied biotic regions in Central America. The peninsula has been
occupied for millennia because the climate of the region supported human habitation and because of its strategic position along the rich Pacific coast. The combination of long-term occupancy by humans and the cataclysmic eruptions of Volcán Cosigüina have produced a heavily impacted landscape. During the 1960s, the University of Kansas conducted multiyear field surveys of the terrestrial mammals on the peninsula and the adjacent mainland to quantify species diversity, relationships, abundances, habitat use, and reproduction. The mammalian fauna of the peninsula contains at least 39 species of terrestrial mammals, which includes 7 orders and 17 families. These include Didelphimorphia (2 species)—Didelphidae, 2; Chiroptera (22)—Emballonuridae, 2; Noctilionidae, 1; Mormoopidae, 1; Phyllostomidae, 12; Vespertilionidae, 3; Molossidae, 3; Carnivora (4)—Procyonidae, 1; Mustelidae, 1; Felidae, 2; Perissodactyla (1)—Tapiridae, 1; Artiodactyla (1)—Cervidae, 1; Rodentia (8)—Sciuridae, 1; Heteromyidae, 1; Muridae, 5; Dasyproctidae, 1; Lagomorpha (1)—Leporidae, 1. We provide new information on distributions, systematics, morphometrics, and natural history of the species of terrestrial mammals on the Cosigüina Peninsula, including a number of new records for the peninsula. We document that diversity and abundances of mammals can be substantial in a heavily impacted landscape. In comparison with five other mammalian faunas in Nicaragua, the Cosigüina fauna is most similar in size and diversity with those from elsewhere in the Pacific lowlands. The fauna from the Cordillera los Maribios, which is composed of the volcanic peaks along the eastern edge of the Pacific Lowlands, has the lowest number of species recorded for any of the six faunas with only 21 species recorded; however, this fauna may be under sampled or the unstable environments offered by these active volcanoes may not support a large or diverse mammalian fauna. The mammalian faunas from the remaining two physiographic regions of Nicaragua—Central Highlands and Atlantic Lowlands—have larger, more diverse faunas than that of the Cosigüina Peninsula and elsewhere in the Pacific lowlands. Three reserves in Nicaragua’s Sistema Nacional de Áreas Protegidas now protect more than one fourth of the peninsula.

The Xenarthrans of Nicaragua

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The mammalian fauna of Nicaragua includes seven species in the order Xenarthra, including the brown-throated three-toed sloth (Bradypus variegatus) in the family
Bradypodidae, Hoffmann’s two-toed sloth (Choloepus hoffmanni) in the family Megalonychidae, the northern naked-tailed armadillo (Cabassous centralis) and nine-banded armadillo (Dasypus novemcinctus) in the family Dasypodidae, and the silky anteater (Cyclopes didactylus) and northern tamandua (Tamandua mexicana) in the family Myrmecophagidae. Additionally, the giant anteater (Myrmecophaga tridactyla) in the family Myrmecophagidae is (or was) certainly part of the fauna of Nicaragua but has yet to be documented there. Based on 133 xenarthran specimens available in museums and our observations, we herein review and provide new information on distributions, systematics, morphometrics, and natural history of these species in Nicaragua. Replacement of the milk dentition in Dasypus novemcinctus is described and illustrated, documenting the most common adult dental formula of i 0/0, c 0/0, p 7/7, m 1/1 = 32.

Los Xenarthra de Nicaragua. La fauna mamífera de Nicaragua incluye siete especies del orden Xenarthra, incluyendo el perezoso de tres dedos (Bradypus variegatus) en la familia Bradypodidae, el perezoso (Choloepus hoffmanni) en la familia Megalonychidae, el armadillo zopilote (Cabassous centralis) y el cusuco (Dasypus novemcinctus) en la familia Dasypodidae, y el tapacara (Cyclopes didactylus) y el oso hormiguero (Tamandua mexicana) en la familia Myrmecophagidae. Además, el oso caballo (Myrmecophaga tridactyla) en la familia Myrmecophagidae es (o fue) ciertamente parte de la fauna de Nicaragua pero todavía no ha sido documentado allá. Basados en 133 especímenes de Xenarthra disponibles en museos y nuestras observaciones, revisamos y proveemos información nueva sobre distribuciones, sistemática, morfométrica y la historia natural de estas especies en Nicaragua. El reemplazo de la dentición láctea en Dasypus novemcinctus se describe e ilustra, documentando la fórmula dental adulta más común de i 0/0, c 0/0, p 7/7, m 1/1 = 32.

The heteromyd rodents from the Mexican state of Puebla

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We examined 300 specimens of the three species of heteromyids collected in 75 localities from the Mexican state of Puebla. Taxonomic recognition to the subspecific level allowed the identification of Perognathus flavus mexicanus, Dipodomys phillipsii oaxacae, D. p. perotensis, Liomys irroratus texensis, L. i. torridus, and, for the first time for the state, L. i. alleni. External and cranial measurements of adult specimens are presented along with data concerning sexual secondary variation in Liomys irroratus. The localities are described according to the characteristics of regional mammalian biogeographic provinces.

Los roedores heterómidos del Estado mexicano de Puebla. Se examinaron 300 ejemplares de heterómidos incluidos en tres especies y procedentes de 75 localidades en el Estado de Puebla. El reconocimiento subespecífico permite identificar a Perognathus flavus mexicanus, Dipodomys phillipsii oaxacensis, D. p. perotensis, Liomys irroratus texensis, L. i. torridus y, por primera ocasión para la entidad, a L. i. alleni. De todos los ejemplares se consignan tanto las medidas externas como las craneales. Hembras y machos de Liomys irroratus presentan bajo dimorfismo sexual secundario. Las localidades de procedencia de los ejemplares examinados se ubican dentro de la regionalización mastofaunística del Estado y se citan las características fundamentales de las provincias respectivas.

Distribución de los armadillos (Mammalia, Dasypodidae) en la región pampeana (República Argentina) durante el holoceno. Interpretación paleoambiental

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El objetivo de este trabajo es reconstruir la historia de la distribución de los armadillos en la región pampeana, particularmente en la provincia de Buenos Aires. Se analizaron los registros de las especies de dasipódidos de 21 yacimientos arqueológicos y paleontológicos. Se registraron: Eutatus seguini, Chaetophractus villosus, C. vellerosus, Zaedyus pichiy, Tolypeutes matacus y Dasypus hybridus. Se realizaron las siguientes interpretaciones: 1) durante el Holoceno temprano se registra, principalmente en el sector de Tandilia y Área Interserrana, la asociación C. villosus – E. seguini, con el agregado de Z. pichiy. Los dasipódidos registrados sugieren condiciones ambientales áridas a semiáridas y, probablemente, temperaturas medias anuales inferiores a las actuales; 2) durante el Holoceno medio se mantiene la asociación C. villosus – Z. pichiy en el centro y sur de la provincia, con una probable retracción de T. matacus en el Área Interserrana y de Tandilia. Esta asociación no refleja el pulso húmedo y cálido propuesto por varios autores, sino un avance de las condiciones patagónicas; 3) el Holoceno tardío se caracteriza principalmente por la asociación C. villosus – Z. pichiy – D. hybridus. En el lapso 3000–1500 años antes del presente se registran, en el nordeste de la provincia, armadillos típicos de climas cálidos del norte (T. matacus y D. hybridus) junto con C. villosus. Contemporáneamente, en el Área Interserrana se mantendrían las condiciones patagónicas, reflejadas por la asociación C. villosus – Z. pichiy. Hacia 1500 años AP la asociación C. villosus – D. hybridus ya se ha instalado en el norte y este de la provincia, destacándose la ausencia de Z. pichiy. Hacia el sur se registra la transición hacia las condiciones templado-húmedas actuales, evidenciada por el avance de D. hybridus.

Distribution of the armadillos (Mammalia, Dasypodidae) in the pampean region (Argentine Republic) during the Holocene. Paleoenvironmental interpretations. Since their first records in the late Miocene (13 millon years) the armadillos constitute one of the principal components of the Pampean region mammal fauna. During the last 10000 years, the distribution of these species in the Pampean region underwent variations as a consequence of climatic and environmental changes. The goal of this paper is to establish the history of the armadillos distribution in the Pampean region, particularly in the Buenos Aires Province. The paleontological and archeological records of the different species are analized, within the paleoenvironmental schemes proposed for the late Pleistocene-Holocene in middle latitudes of Argentina. Twenty one archeological and paleontological sites were considered and the following taxa were recorded: Eutatus seguini (an extinct species) and Chaetophractus villosus, C. vellerosus, Zaedyus pichiy, Tolypeutes matacus and Dasypus hybridus (all living species). The following conclusions can be inferred: 1) During the early Holocene the association C. villosus – E. seguini, with the addition of Z. pichiy, is present in Tandilia and Interserrana areas. The armadillos recorded in this period suggest arid and semiarid environmental conditions and, probably, annual mean temperatures lower than the present ones. 2) During the middle Holocene the association C. villosus – Z. pichiy is still present in central and southern Buenos Aires Province, with a probable retraction of T. matacus in Tandilia and Interserrana areas. This association indicates an advance of the Patagonic conditions; it doesn’t show the warm and humid pulse pointed by other authors. 3) The record of the late Holocene is characterized mainly by the association C. villosus – Z. pichiy – D. hybridus. Between 3000–1500 years before present, armadillos typical of the northern warm climates (T. matacus and D. hybridus) along with C. villosus, are recorded in the northeast of the province. At the same time, Patagonic conditions are still present in the Interserrana Area, reflected by the presence of C. villosus – Z. pichiy. Around 1500 years before present, the association C. villosus – D. hybridus is already established in northern and eastern Buenos Aires, whereas Z. pichiy is absent. A transition toward the present humid-temperate conditions is recorded to the south; this is shown for the range expansion of D. hybridus.