RESUMEN Cerradomys goytaca es un roedor cricetideo endémico de las formaciones de Restinga del sureste de la Selva Atlantica. Es conocido solo en cinco localidades, y se considera en peligro de extinción. Aquí, proporcionamos nuevos datos sobre C. goytaca de una localidad adicional en el estado de Río de Janeiro. El presente registro proporciona nuevos datos del hábitat y representa el límite geográfico más occidental de esta especie poco conocida.

ABSTRACT Cerradomys goytaca is a cricetid rodent endemic to "Restinga" formations from southeastern Atlantic Forest. It is known from only five localities, and it is considered endangered of extinction. Herein, we furnish new data on C. goytaca from an additional locality in Rio de Janeiro state. The present record provides new data on habitat and represents the westernmost geographic limit of this poorly known species.

ABSTRACT The Anthropocene brought an accelerated risk of extinction for species across the globe. However, extinction proneness is not even across groups. Past and current events show large-sized mammals at greater extinction risk than smaller ones. For practical reasons, conservation actions tend to focus on the species level; therefore, well-founded species limits are pivotal. Since 2005, the number of known mammal species is about 20% higher but largely due to taxonomic discoveries in small-sized taxa. Here we review the recent taxonomic advances on medium- and large-sized mammals (MLM) from the Neotropics, and discuss misperceptions concerning the taxonomy stability in this group and how this may hinder proper conservation actions. We advocate that apparent taxonomic inertia toward large-sized mammals is partly related to limited systematic inquiry rather than representing an accurate knowledge of their diversity. Fortunately, this scenario has slowly changed in recent years. Linked to integrative analyses that took place during the 21st century, the Neotropical region represents a major example of recent growth in MLM diversity. Taxonomic novelties were found in eight orders of MLM and occurred across taxonomic ranks, from family to subspecies. Most changes comprise subspecies or synonyms elevated to full species, but new taxa of Artiodactyla, Carnivora, Lagomorpha, Pilosa, Primates, Perissodactyla, and large rodents have also been discovered. Recent reshuffles in MLM classification clearly illustrate the risk that bias in taxonomy studies can bring to conservation. Considering the new findings, some species previously labeled as “least concern” for conservation, stand now in some level of threat. This appraisal challenges the misperception of MLM as well-known and shows that taxonomy is a conservation issue.

RESUMO Monodelphis glirina é endêmica da Amazônia e aspectos dos seus hábitos de vida e história natural são pouco conhecidos. Dados sobre a espécie foram coletados no norte de Mato Grosso, Brasil, incluindo observações sobre seu comportamento e simpatria com congêneres. Durante 10 expedições e com um esforço de 3.680 baldes-dia, foram capturados 29 M. glirina, três M. saci e um M. emiliae. Adultos representaram 82,8% das capturas de M. glirina e a razão sexual foi três machos para cada fêmea. A captura de jovens e fêmeas lactantes foi sazonal, uma vez que ambos foram capturados apenas na estação chuvosa. Observamos três eventos de M. glirina predando roedores em pitfall traps, todos com o mesmo comportamento de alimentação. Também registramos um individuo escalando uma árvore durante a noite, incluindo um video. Nosso trabalho contribui para uma melhor compreensão da ecologia desse gênero altamente diversificado e ainda pouco conhecido.

ABSTRACT Monodelphis glirina is endemic to the Amazon and its life habits and natural history are poorly known. Data on the species were collected in northern Mato Grosso, Brazil, including observations on its behavior and simpatry with congeners. During 10 expeditions and with an effort of 3,680 buckets-day, 29 M. glirina, three M. saci and one M. emiliae individuals were captured. Adults accounted for 82.8% of M. glirina captures, with a sex ratio of three males for each female. Capture of young and lactating females was seasonal, as both were captured only in the rainy season. We observed three events of M. glirina preying on rodents in pitfall traps, all with the same feeding behavior. We also report an individual climbing a tree at night, including a video recording. Our report contributes to a better understanding of the ecology of this highly diversified and still poorly known genus.

Resumo 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.

Abstract The state of Mato Grosso is one of the largest (903 357 km.) 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.

Abstract: The South American genus Calomys exhibits a disjunct distribution with most species inhabiting grasslands, savannas, and forest edges from ca. latitude 8° S in the highlands of Peru and the Caatinga of Brazil to ca. latitude 16° S in central Bolivia, and from there south into Argentine Patagonia. Only a single species (Calomys hummelincki) occurs in open habitats in northern South America. We report the first known specimen of Calomys hummelincki for Brazil. The specimen is deposited in the mammal collection of Museu de Zoologia da Universidade de São Paulo, São Paulo. It is a young adult female with two embryos collected on 13 March 1989 by C. M. Carvalho at Fazenda Salvamento, Roraima state, during a herpetofaunal survey. The specimen shares qualitative and quantitative characters with specimens from Venezuela and Curaçao, but also differs substantially in others. The record presented herein extends the known range of the species about 630 km southeast-ward from the nearest previous record (in Venezuela, Estado Bolívar, Sipao). This new record was obtained in a locality representative of the savannas of the Rio Branco - Rupununi region that supports a poorly known, but distinctive mammalian fauna. This entire eco-region represents a piece of the biogeographic puzzle resulting from the climate-dependent vegetation shifts that dominated the Quaternary of South America. This new record highlights the need to investigate and protect the biodiversity of the Rio Branco-Rupununi savannas.

Resumen: El género Sudamericano Calomys presenta una distribución discontinua, con la mayoría de sus especies presentes en los pastizales, sabanas y bordes del bosque desde 8 °S latitud S en el altiplano de Perú y la Caatinga de Brasil hasta lat 16 °S en el centro de Bolivia y desde allí hacia el sur, hacia la Patagonia Argentina. En este trabajo presentamos el primer registro de Calomys hummelincki para Brasil, basado en un espécimen que se encuentra depositado en la colección de mamíferos del Museo de Zoología de la Universidade de São Paulo, São Paulo. Específicamente, se trata de una hembra adulta joven con dos embriones y que fue atrapada el 13 de marzo de 1989 por C. M. Carvalho en la Fazenda Salvamento, en el estado de Roraima, durante un levantamiento de herpetofauna. Este espécimen comparte caracteres métricos y cualitativos con individuos de la misma especie y de poblaciones en Venezuela y Curaçao, aunque al mismo tiempo, difiere substancialmente en otros. El registro presentado en este trabajo extiende en alrededor de 630 km SE la distribución de la especie desde el registro más cercano (Venezuela, Estado Bolívar, Sipao). El registro aquí reportado proviene del sistema de sabanas denominadas del Río Branco-Rupununi, un ecosistema que contiene una fauna de mamíferos única y poco conocida. Este ecosistema representa una pieza importante en el rompecabezas biogeográfico que resultó de los cambios de vegetación que dominaron el Cuaternario de Sudamérica. Se destaca la necesidad de estudiar y proteger la biodiversidad de las sabanas Rio Branco-Rupununi.