Contribution to the knowledge about mammal collections in Brazil

We provide a brief introduction on the importance and use of scientific collections and a general overview of the articles that are part of the special issue of the Brazilian Journal of Mammalogy on Brazilian mammal collections. The 19 articles that comprise this issue refer to collections distributed across eight Brazilian states. Most of the collections hold specimens of living mammals, and two of them are paleontological collections. Two articles address specific orders of mammals, while the rest present data for all the orders. We hope that this issue represents a significant contribution to efforts to preserve Brazilian scientific collections, providing a more comprehensive view of their importance and the current and potential use of the specimens preserved therein.

Apresentamos uma breve introdução sobre a importância e uso de coleções científicas e um panorama geral dos artigos que fazem parte do número especial do Brazilian Journal of Mammalogy sobre coleções brasileiras de mamíferos. Os 19 artigos abrangem coleções distribuídas em oito estados da federação. Em sua maioria tratam de mamíferos viventes, sendo dois referentes a coleções paleontológicas. Dois artigos abordam ordens específicas de mamíferos e os demais apresentam dados para todas as ordens. Esperamos que este número represente uma contribuição significativa aos esforços para preservar as coleções científicas nacionais, fornecendo uma visão mais abrangente acerca das coleções e do uso atual e potencial dos espécimes nelas preservados.

Expert range maps of global mammal distributions harmonised to three taxonomic authorities.

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 macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW). Location: Global. Taxon: All extant mammal species. Methods: Range maps were digitally interpreted, georeferenced, error-checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species). Results: Range maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non-commercial use. Main conclusion: Expert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad-scale characterizations and model-based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species-level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control.

Neotropical carnivores: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non‐detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non‐governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peerreviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non‐detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio‐temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other largescale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data.

Abundance of small mammals in the Atlantic Forest (ASMAF): a data set for analyzing tropical community patterns.

Local abundance results from the interaction between populational and environmental processes. The abundance of the species in a community is also one of the most basic descriptors of its structure. Despite its importance, information about species abundances is fragmentary, creating a knowledge gap about species abundances known as the Prestonian Shortfall. Here we present a comprehensive data set of small mammal abundance in the Atlantic Forest. Data were extracted from 114 published sources and from unpublished data collected by our research groups spanning from 1943 to 2017. The data set includes 1,902 records of at least 111 species in 155 localities, totaling 42,617 individuals represented. We selected studies that (1) were conducted in forested habitats of the Atlantic Forest, (2) had a minimum sampling effort of at least 500 trap-nights, and (3) contained species abundance data in detail. For each study, we recorded (1) latitude and longitude, (2) name of the locality, (3) employed sampling effort, (4) type of traps used, (5) study year, (6) country, and (7) species name with (8) its respective abundances. For every locality, we also obtained information regarding its (9) ecoregion, (10) predominant vegetation type, and (11) biogeographic subdivision. Whenever necessary, we also (12) updated the species names as new species were described and some genera suffered taxonomic revision since the publication. The localities are spread across the Atlantic Forest and most of the small mammal species known to occur in Atlantic Forest are present in the data set, making it representative of communities of the entire biome. This data set can be used to address various patterns in community ecology and geographical ecology, as the relation between local abundance and environmental suitability, hypothesis regarding local and regional factors on community structuring, species abundance distributions (SAD), functional and phylogenetic mechanisms on community assembling.

Orbit orientation in didelphid marsupials (Didelphimorphia: Didelphidae).

Usually considered a morphologically conservative group, didelphid marsupials present considerable variation in ecology and body size, some of which were shown to relate to morphological structures. Thus, changes on orbit morphology are likely and could be related to that variation. We calculated orbit orientation in 873 specimens of 16 Didelphidae genera yielding estimates of orbits convergence (their position relative to midsagittal line) and verticality (their position relative to frontal plane). We then compared similarities in these variables across taxa to ecological, morphological and phylogenetic data to evaluate the influencing factors on orbit orientation in didelphids. We found an inverse relation between convergence and verticality. Didelphids orbits have low verticality but are highly convergent, yet orbit orientation differs significantly between taxa, and that variation is related to morphological aspects of the cranium. Rostral variables are the only morphological features correlated with orbit orientation: increasing snout length yields more convergent orbits, whereas increase on snout breadth imply in more vertical orbits. Size and encephalization quotients are uncorrelated with orbit orientation. Among ecological data, diet showed significant correlation whereas locomotion is the factor that less affects the position of orbits. Phylogeny is uncorrelated to any orbital parameters measured. Ecological factors seemingly play a more important role on orbit orientation than previously expected, and differentiation on orbit orientation seems to be more functional than inherited. Thus, despite the apparent homogeneity on didelphid morphology, there is subtle morphological variability that may be directly related to feeding behavior.

First evidence of gregarious denning in opossums (Didelphimorphia, Didelphidae), with notes on their social behaviour.

The Didelphidae are considered solitary opossums with few social interactions, usually limited to mating-related or mother-pouch young interactions. Anecdotal reports suggest that additional interactions occur, including den sharing by a few individuals, usually siblings. Here, we report novel observations that indicate opossums are more social than previously thought. These include nest sharing by males and females of Marmosa paraguayana, Gracilinanus microtarsus and Marmosops incanus prior to the onset of the breeding season and without signs of sexual activity; this is taken to indicate early pair-bonding matching and cooperative nest building. We also recorded den sharing among recently weaned siblings of Didelphis aurita and Caluromys philander. In addition, we observed 13 individuals of Didelphis albiventris representing three age classes resting without agonistic interactions in a communal den. These are the first reports of gregarious behaviour involving so many individuals, which are either unrelated or represent siblings from at least two litters, already weaned, sharing the same den with three adults. Sociality in opossums is probably more complex than previously established, and field experimental designs combining the use of artificial nests with camera traps or telemetry may help to gauge the frequency and extent of these phenomena.

Distribution of Oecomys catherinae Thomas, 1909 (Rodentia: Cricetidae) in northeastern Brazil with karyotypical and morphometrical notes / Distribuição de Oecomys catherinae Thomas, 1909 (Rodentia: Cricetidae) no nordeste do Brasil com notas morfométricas e cariotípicas

The genus Oecomys Thomas, 1906 is currently composed of 16 species with unclear taxonomy and poorly known geographic limits. O. catherinae Thomas, 1909 is known to occur within the Brazilian Atlantic Forest from the states of Santa Catarina to Pernambuco (where the northernmost previously known specimen of Oecomys in the Atlantic forest was recorded), and along riverine forest into the Cerrado. To gain a greater understanding of its geographical and ecological distribution (mainly in Northeastern Brazil) and of its taxonomic characterization, we provide a short review of karyotypical and morphometrical data from specimens collected within the distribution range of the species. Specimens presented 2n = 60 and AN varying between 62 and 64. A table with external and cranial measurements of the analyzed specimens is provided. In this paper we also report the presence of O. catherinae in the semi-deciduous forests of the state of Paraíba, representing the northernmost records of the species in the Atlantic forest and thereby extending its known geographical limits.

Oecomys Thomas, 1906 é um gênero atualmente composto por 16 espécies reconhecidas que apresentam taxonomia e distribuições geográficas ainda incertas. O. catherinae Thomas, 1906 é a espécie que ocorre ao longo da Floresta Atlântica brasileira dos estados de Santa Catarina a Pernambuco, onde se encontra o registro prévio mais ao norte para Oecomys na Floresta Atlântica, e ao longo de florestas de galeria no Cerrado. Pretendendo esclarecer aspectos relacionados à distribuição geográfica e ecológica de O. catherinae, com ênfase na região nordeste do Brasil, e auxiliar na sua caracterização taxonômica, fornecemos um breve resumo de dados morfométricos e cariotípicos de indivíduos coletados em diversos trabalhos ao longo da área de ocorrência da espécie. Os espécimens apresentaram 2n = 60 e NA variando entre 62 e 64. Uma tabela de medidas corporais externas e cranianas dos indivíduos analisados é fornecida. Também registramos pela primeira vez a presença de O. catherinae nas florestas semi-deciduais do estado da Paraíba, sendo atualmente os registros mais ao norte da espécie na Floresta Atlântica, estendendo os limites geográficos conhecidos para a espécie.

Distribution extension and sympatric occurrence of Gracilinanus agilis and G. microtarsus (Didelphimorphia, Didelphidae), with cytogenetic notes / Extensão da distribuição e ocorrência em simpatria de Gracilinanus agilis e G. microtarsus (Didelphimorphia, Didelphidae) com notas citogenéticas

Gracilinanus microtarsus, from the Atlantic Forest and G. agilis, widespread in central Brazil in the Cerrado and in the northeastern Caatinga are two small Neotropical arboreal opossum species not frequently recorded in simpatry. Here we report eight G. agilis specimens from three localities and 17 G. microtarsus, from 10 localities, all in Minas Gerais, Rio de Janeiro and Bahia states. Species proper identification followed diagnostic characters as appearance of dorsum pelage, ocular-mark, ears and tail lengths and size proportion of the posteromedial vacuities in cranium. Chromosomes in metaphases of five specimens were obtained for both species. Our records extend the previous known geographical distribution of G. microtarsus to Chapada Diamantina, in Bahia State and report the occurrence of both species in simpatry. G. microtarsus, in coastal area, was captured in dense ombrophilous and in semideciduous forests, in deciduous seasonal forest and Cerradão in Chapada Diamantina. G. agilis was recorded in gallery forests of Cerrado and very green and dense bush formation of Caatinga. Autosomal complement showed the same diploid and autosomal number already described for both species (2n = 14, NA = 24). Measurements are according to those given in literature and pelage characteristics were useful for the correct species identification. Here we report both G. agilis, described to be endemic to the Cerrado/Caatinga, in opposite to G. microtarsus, considered to be endemic to Atlantic Forest occurring in simpatry in two localities of the Cerrado. Such results indicates that long term trapping effort are necessary to a better definition of species taxonomy, distribution patterns along time and comprehensive understanding how anthropic environmental changes can be interfering in their evolutionary history.

Gracilinanus microtarsus, da Mata Atlântica e G. agilis, amplamente distribuído no Brasil central, tanto no Cerrado como na Caatinga são duas pequenas espécies de cuícas arbóreas. As duas espécies são raramente registradas em simpatria. Aqui registramos oito espécimes de G. agilis coletadas em três localidades e 17 G. microtarsus, de dez localidades, todas nos estados de Minas Gerais, Rio de Janeiro e Bahia. A correta identificação baseou-se nos caracteres diagnósticos como aparência da pelagem dorsal, marca escura na região óptica, comprimentos da orelha e cauda, bem como a proporção do tamanho das vacuidades posteromediais do crânio. Cromossomos metafásicos de cinco indivíduos foram obtidos. Nossos registros aumentam a distribuição geográfica previamente conhecida de G. microtarsus para a Chapada Diamantina, no estado da Bahia, e reporta a ocorrência de simpatria. G. microtarsus, na área costeira, foi capturado em florestas ombrófila densa e semidecidual em floresta estacional decidual e Cerradão na Chapada Diamantina. G. agilis foi registrado em matas de galeria do Cerrado, e formações densas de vegetação arbustiva verde na Caatinga. O complemento autossômico mostrou os mesmos números diplóides e autossômicos já registrados para as duas espécies (2n = 14, NA = 24). Medidas corpóreas estão de acordo com a literatura, e as características de pelagem foram ferramentas úteis para a correta identificação das espécies. Aqui registramos G. agilis, descrita como sendo uma espécie endêmica do Cerrado e da Caatinga, em oposição a G. microtarsus, considerada como endêmica da Mata Atlântica ocorrendo em simpatria em duas localidades do Cerrado. Tais resultados indicam que esforços continuados de coleta são necessários para uma melhor definição da taxonomia das espécies, dos padrões de distribuição ao longo do tempo e uma melhor compreensão de como as mudanças ambientais antrópicas estão interferindo em suas historias evolutivas.

Evolution of scapula size and shape in didelphid marsupials (Didelphimorphia: Didelphidae).

The New World family Didelphidae, the basal lineage within marsupials, is commonly viewed as morphologically conservative, yet includes aquatic, terrestrial, scansorial, and arboreal species. Here, I quantitatively estimated the existing variability in size and shape of the Didelphidae scapula (1076 specimens from 56 species) using geometric morphometrics, and compared size and shape differences to evolutionary and ecologic distances. I found considerable variation in the scapula morphology, most of it related to size differences between species. This results in morphologic divergence between different locomotor habits in larger species (resulting from increased mechanical loads), but most smaller species present similarly shaped scapulae. The only exceptions are the water opossum and the short-tailed opossums, and the functional explanations for these differences remain unclear. Scapula size and shape were mapped onto a molecular phylogeny for 32 selected taxa and ancestral size and shapes were reconstructed using squared-changed parsimony. Results indicate that the Didelphidae evolved from a medium- to small-sized ancestor with a generalized scapula, slightly more similar to arboreal ones, but strikingly different from big-bodied present arboreal species, suggesting that the ancestral Didelphidae was a small scansorial animal with no particular adaptations for arboreal or terrestrial habits, and these specializations evolved only in larger-bodied clades.