The Neotropics harbors a high diversity of species and several hypotheses have been proposed to account for this pattern. However, while species of forested domains are frequently studied, less is known of species from open vegetation formations occupying, altogether, a larger area than the Amazon Forest. Here we evaluate the role of historical barriers and the riverine hypothesis in the speciation patterns of small mammals by analyzing an ancient rodent lineage (Thrichomys, Hystricomorpha). Phylogenetic and biogeographic analyses were carried out with mitochondrial and nuclear DNA markers to analyze the evolutionary relationships between Thrichomys lineages occurring in dry domains along both banks of the Rio São Francisco. This river is one of the longest of South America whose course and water flow have been modified by inland tectonic activities and climate changes. Molecular data showed a higher number of lineages than previously described. The T. inermis species complex with 2n = 26, FN = 48 was observed in both banks of the river showing a paraphyletic arrangement, suggesting that river crossing had occurred, from east to west. A similar pattern was also observed for the T. apereoides complex. Thrichomys speciation occurred in Late Miocene when the river followed a different course. The current geographic distribution of Thrichomys species and their phylogenetic relationships suggested the existence of frequent past connections between both banks in the middle section of the Rio São Francisco. The extensive palaeodune region found in this area has been identified as a centre of endemism of several vertebrate species and is likely to be a center of Thrichomys diversification.

Abstract:The Volta Grande Environmental Unity represents one of the few remnants of Cerrado protected by a reserve in the Triângulo Mineiro region, municipalities of Conceição das Alagoas (19°55' S, 48°23' W) and Miguelópolis (20°12' S, 48°03' W), in the states of Minas Gerais and São Paulo, respectively. The mammalian fauna of this reserve was inventoried between 2003 and 2004 to generate estimates about taxonomic composition, richness, and abundance of species. A sampling effort of 832 trapping-nights resulted in 24 species recorded. Cumulative curves suggest that the overall inventory is not complete and that more species are likely to be registered. The majority of species recorded is widespread along the Cerrado, but include some noteworthy records of endangered species, such as the Giant anteater (Myrmecophaga tridactyla) and the Manned wolf (Chrysocyon brachyurus). The record of the arboreal cricetid rodent Oecomys bicolor represents a slight extension of the southeastern limit of its distribution.

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Thrichomys fosteri (Rodentia, Echimyidae) is a terrestrial spiny rat displaying frugivorous/ herbivorous diet. Then, why eventually this terrestrial species uses the understory? Here, we report two events of use of understory for fruit feeding by the spiny rat. Monthly from October 2015 through July 2016, we sampled three sites in one woodland savannah fragment in the Pantanal ecoregion. Each site was 1 km apart from each other, and present five camera traps on understory (1.5 m height) in front of different fruit plant species. With an effort of 350 camera trap-days, we recorded twice the punaré on branch of Randia armata (Rubiaceae) feeding on its fruits. Our results highlight a feeding behaviour on understory by the terrestrial spiny rat, which contribute to the understanding of the species' natural history as well as point out questions for further investigations.

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Agoutis, Dasyprocta spp., are medium-sized rodents distributed in Neotropical region. Their diet is usually described as granivorous/frugivorous, and agoutis are recognised as important seed dispersers. Here, we present two spatially and temporally independent records of egg predation by Azara's agouti, Dasyprocta azarae, in fragments of Cerrado savanna forest. In both cases, the agoutis ingested quail eggs that had been placed in artificial nests at ground level, 100 m from the edge of the forest. As Dasyprocta is a herbivorous rodent, this predatory behaviour is unexpected and may represent an opportunistic foraging strategy. These observations provide important new insights into the feeding biology of agoutis and highlight the value of camera traps as a tool for the collection of data on the behavioural ecology and natural history of vertebrates in general.

The state of Goiás, in central Brazil, is covered mainly by the Cerrado domain, with the Alto Paraná Atlantic Forest occupying its central-southern portion. Goiás is one of the 20 Brazilian federative units without a mammal checklist. In this study, we provide the first checklist of mammals from Goiás state. We recorded mammal species based primarily on the analysis of specimens housed in scientific collections as well as on literature with associated voucher material. We listed 191 mammalian species belonging to 125 genera, 31 families and 10 orders, which represents 25.2% of the mammal species occurring in Brazil. The most speciose orders were Chiroptera (90 spp.), followed by Rodentia (43 spp.), Carnivora (19 spp.) and Didelphimorphia (17 spp.). The following orders accounted for a smaller portion of the state diversity: Cetartiodactyla (7 spp.), Cingulata (7 spp.), Primates (4 spp.), Pilosa (2 spp.), Lagomorpha (1 sp.), and Perissodactyla (1 sp.). A total of 28 species (14.7%), mainly represented by medium and large-sized mammals, are nationally threatened while 12 (6.3%) are globally threatened. Our results indicate great portions of the state lacking a proper survey of mammals, especially the northwestern portion. We discuss species richness, distribution and conservation status of the mammals of Goiás state in national and regional scenarios. We highlight the need for mammal inventories based on complementary survey techniques with the collection of vouchers in order to provide karyologic, molecular, morphologic, parasitologic, and ecological data. These informations are the basis for integrative studies that lead to the understanding of current mammalian richness and diversity. Indeed, knowledge on species richness distribution in the state will guide conservation strategies, especially in areas undergoing habitat loss and fragmentation, such as the central-southern portion of Goiás.

The replacement of natural landscapes by anthropic environments has led to habitat loss and consequently, to the decline and extinction of many species populations. Several strategies, such as the creation of protected areas (PAs) and payment for ecosystem services have been adopted to mitigate the consequences of this biodiversity crisis. In Rio Verde, Goiás, Brazil, a Water Producer Program (WPP) was established, which provides payment for ecosystem services for the maintenance of riparian vegetation in the region of the Ribeirão Abóbora, a river which supplies the city and metropolitan area. In the absence of environmental diagnostic studies in the region, this present study contributes to reducing some knowledge gaps, through the: (i) characterization of the landscape in the WPP area, (ii) characterization of species of fauna (amphibians, birds, fish, and medium and large terrestrial mammals) and woody flora that occur in this area, and (iii) comparison of species diversity (fauna and flora) found in our study area with the diversity observed in the Cerrado protected area network. Our results reveal a low native vegetation cover (~21% of total area), but we recorded 300 total species: 20 species of anuran amphibians, 100 birds, 10 fish, 16 terrestrial mammals (medium and large), and 154 woody plants. Our sample comprises species considered endemic to the Cerrado (e.g., Anuran - Barycholos terntezi and Mammal - Callithrix penicillata), threatened species (e.g., Mammals - Herpailurus yagouaroundi, Myrmecophaga tridactyla and Tapirus terrestris), and exotic invasive species (Mammal - Sus scrofa). The results presented in this study are relevant and may help in the proposal of management actions within the scope of this important program of payment for environmental services.