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Aim To investigate the biogeographical history of the Pantepui region based on the phylogenetic relationships and divergence dates of a tepui-endemic small mammal: the Roraima mouse, Podoxymys roraimae. This mouse is one of the rarest and most restricted mammals in terms of geographical distribution, and its evolutionary position has never been evaluated within a rigorous phylogenetic framework. Location The Pantepui biogeographical region of northern South America, which harbours a remarkable flora and fauna in one of the most dramatic landscapes on Earth. Methods We used maximum-likelihood and Bayesian analyses of mitochondrial (cytb) and nuclear (irbp) DNA sequences from a specimen of P. roraimae to infer phylogenetic affinities and estimate divergence times of Podoxymys from its closest relatives based on a relaxed molecular clock model. Results Podoxymys lies within the Akodontini tribe of the rodent subfamily Sigmodontinae, closely related to Thalpomys and Necromys, two taxa found on the Brazilian Plateau. The divergence of Podoxymys from its closely related genera was estimated at 2.47–3.68 Ma, at the end of the Neogene (Pliocene) and before the start of the Pleistocene climatic oscillations. Main conclusions Podoxymys roraimae is a relict species restricted to tepui summits, and its closest relatives are taxa found in open-vegetation biomes, especially the Cerrado vegetation on the Brazilian Plateau. Our results do not conform to the predictions of currently proposed models of Pantepui faunal evolution, but instead indicate a possible relationship between the Guiana and Brazilian shields during the Pliocene.

541. Hairy-eared Cerrado Mouse Thalpomys lasiotis French: Akodon a oreilles velues / German: Haarohr-Cerrado-Feldmaus / Spanish: Ratén del Cerrado de oeja peluda Other common names: Hairy-eared Akodont Taxonomy. Habrothrix lasiotis Winge, 1887, Lagoa Santa, Minas Gerais, Brazil. Thalpomys lasiotis is the type species of the genus. Monotypic. Distribution. EC & SE Brazil (Bahia, Minas Gerais, and Sao Paulo states, and Distrito Federal), with an isolated record in W Brazil (Rondonia State); range may extend to Matto Grosso State. Descriptive notes. Head-body 76 mm (mean value for males), tail 46 mm, ear 13 mm, hindfoot 16 mm; weight 21 g. Males seem to be slightly larger than females. The Hairy-eared Cerrado Mouse is a smaller version of the Common Cerrado Mouse (1: cerradensis) but with longer and more lax fur and more saturate color throughout. Chromosomal complement is 2n = 38, FN = 38. Habitat. Open grasslands (“campo limpo”), open grasslands mixed with low shrubs (“campo cerrado”), open grasslands with scattered shrubs and trees (“campo sujo”), wet grasslands with water-saturated soil (“campo umido”), and wild grasslands with small natural earthen mounds without trees or underbrush (“campo de murundus”) in the Cerrado biome. The Hairy-eared Cerrado Mouse seems to have a patchy distribution occurring in higher densities in seasonally flooded habitats like campos de murundus. Food and Feeding. The Hairy-eared Cerrado Mouse is considered to be insectivorous— omnivorous due to the high proportion of insect fragments found in its feces (70%). Weights of Hairy-eared Cerrado Mice vary little between seasons suggesting that diets also vary little seasonally. Breeding. The Hairy-eared Cerrado Mouse apparently breeds differentially according to distribution; reproductive activity was recorded during wet season (November—February) in east-central Brazil but during end of dry season (August-October) in central Brazil. Overall, reproductive individuals occur in August—May. Litters have 2-3 young. Activity patterns. The Hairy-eared Cerrado Mouse is nocturnal and terrestrial. Movements, Home range and Social organization. Mean home range of 26 Hairy-eared Cerrado Mice (both sexes) was 2278 m?; home ranges of males and females did not different. No differences in distances moved between dry and rainy seasons (both sexes) and mean distance moved by males between seasons were found. Distances moved by two males were more than 1 km, suggesting important displacement in search of food, females, or territories. The Hairy-eared Cerrado Mouse had a residency of 2-9 months in natural habitats. Densities in winter were 0-5-0-6 ind/ha. The Hairy-eared Cerrado Mouse occurs in higher numbers during dry season, and higher population estimates and densities were observed in June-October. Higher density recorded during dry season seems to be related to availability of grass seeds. Status and Conservation. Classified as Least Concern on The IUCN Red List. Bibliography. Alho & Pereira (1985), Andrade et al. (2004), Bonvicino & Bezerra (2003), Dietz (1983), Hershkovitz (1990a), Lacher et al. (1990), Marinho-Filho, Bonvicino & Vieira (2008b), Pardinas & Teta (2015¢), Ribeiro & Marinho-Filho (2005), Ribeiro et al. (2011), Santos & Henriques (2010), Thomas (1916d), Vieira (1997)., Published as part of Don E. Wilson, Russell A. Mittermeier & Thomas E. Lacher, Jr, 2017, Cricetidae, pp. 204-535 in Handbook of the Mammals of the World – Volume 7 Rodents II, Barcelona :Lynx Edicions on page 468, DOI: 10.5281/zenodo.6707142

540. Common Cerrado Mouse Thalpomys cerradensis French: Akodon du Cerrado / German: Cerrado-Feldmaus / Spanish: Raton del Cerrado comun Other common names: Cerrado Akodont, Cerrado Mouse Taxonomy. Thalpomys cerradensis Hershkovitz, 1990, Parque Nacional de Brasilia, 1100 m, Distrito Federal, Brazil. This species is monotypic. Distribution. C Brazil (Mato Grosso, Goias, and Bahia states, and Distrito Federal). Descriptive notes. Head-body 90-109 mm, tail 51-70 mm, ear 14-17 mm, hindfoot 18-21 mm; weight 26-40 g. The Common Cerrado Mouse is moderately small, with overall pale or bright phaeomelaninic color and well-haired tail ¢.65% of head—body length. Ears are of medium length, rounded, and covered by short hairs on both surfaces. Pes and manus have ungual tufts shorter than claws. The Common Cerrado Mouse is larger than the Hairyeared Cerrado Mouse (1. lasiotis) and has dense and stiff pelage; dorsal surface of head and body is generally tawny; sides of body are paler than back; chin is pale buff; check and eye-ring are ocherous orange; vibrissae are short, extending to bases of ears; tail is brownish above and pale buff below; hindfoot is small and pale buff above, with outer toes short; and claws are c.1 mm. There are three pairs of mammae (one pectoral, one abdominal, and one inguinal). Chromosomal complement is 2n = 36, FN = 34. Habitat. Open grasslands (“campo limpo”), wet prairies with palms (‘veredas”), and sparsely wooded savannas in Cerrado biome. Food and Feeding. No information. Breeding. No information. Activity patterns. The Common Cerrado Mouse is more active immediately after sunset and in the last three hours before sunrise. It is terrestrial. Movements, Home range and Social organization. The Common Cerrado Mouse is one of the first to recolonize burned grasslands in the Cerrado, reaching population peaks before two years postfire. Status and Conservation. Classified as Least Concern on The IUCN Red List. Bibliography. Andrade et al. (2004), Bonvicino & Bezerra (2003), Henriques et al. (2006), Hershkovitz (1990a), Marinho-Filho, Bonvicino & Vieira (2008a), Marinho-Filho, Rodrigues & Juarez (2002), Pardinas & Teta (2015c), Vieira & Baumgarten (1995)., Published as part of Don E. Wilson, Russell A. Mittermeier & Thomas E. Lacher, Jr, 2017, Cricetidae, pp. 204-535 in Handbook of the Mammals of the World – Volume 7 Rodents II, Barcelona :Lynx Edicions on page 468, DOI: 10.5281/zenodo.6707142

Hairy-eared cerrado mouse Thalpomys lasiotis is an endemic species of the cerrado biome. It can be found in open habitats, but its distribution is patchy and population numbers are unknown. In this paper, we describe, for the first time, aspects related to the ecology and natural history of T. lasiotis, detailing demographic parameters such as population densities, reproduction, home range, and longevity of this endemic and rare species. We captured, marked, and recaptured 55 individuals of T. lasiotis in Aguas Emendadas Ecological Station, located in the northeast of the Federal District, Brazil. We found significant differences on population numbers and densities between the dry and wet seasons. Densities and population numbers apparently are affected by the seasonality of food resources. Moreover, the breeding season is seasonal, and both males and females were reproductively active during the wet season. T. lasiotis showed a permanence time ranging from 2–9 months, which means that individuals can survive for at least 9 months in natural habitats. The home ranges of males and females of T. lasiotis were not significantly different. However, males have larger home ranges than females and the mean distance moved by males was higher than the distance moved by females, which is consistent with the hypothesis that males belonging to polygynous species tend to move greater distances to avoid agonistic encounters and to search sexual partners.

We describe the karyotype ofThalpomys species, from different Brazilian localities of the Cerrado.Thalpomys cerradensis Herskovitz, 1990 showed 2n=36, FN=34 andT. lasiotis Thomas, 1916 2n=38, FN=38. Comparisons of G-band karyotypes showed evident inter-specific homologies indicating that their chromosome complements could be derived from one another by two presumed rearrangements. Both species showed pericentromeric C-band regions in almost all chromosomes but a comparison with CMA3/DA/DAPI staining indicated that the molecular content of heterochromatic regions was different.T. lasiotis specimens from two different localities differed in the morphology of the X chromosome due to the presence of a short heterochromatic arm. These chromosome types are apparently fixed in each population rather than maintained as a polymorphic variation. Phylogenetic analyses supported the monophyly of the genusThalpomys but was not capable of elucidating its phylogenetic relationship to other Akodontini rodents. These analyses also showed inter-individual variation inT. lasiotis, even within a given population. Phylogenetic analyses placedT. lasiotis specimens with different karyotypes in different monophyletic branches. Molecular and karyologic data confirmed the identity of the genusThalpomys.

The Cerrado biome is a complex of open forests, gallery forests and savanna vegetation that harbours about 60 species of small mammals. Despite the frequent occurrence of fire in this habitat, few studies have analysed its effects on the small mammal communities in the Cerrado. The purpose of this study was to compare small mammal communities of two Cerrado areas with different fire frequencies (2–3 years or more than 18 years since the last fire). Species diversity, species composition, and relative abundance of the most common species of these communities were analysed in both areas before and after fire. One trapping grid was established in each of the two areas. These areas were sampled monthly or bi-monthly during 1 year before and 1 year after prescribed fires. Both areas had communities with similar species composition, but the protected site had more species, before and after fire (seven and eight, respectively), than the frequently burned site (five and six species, respectively). Both sites showed significant post-fire changes for a short time period (3 months), but only the area that had been protected against fire for more time showed significant post-fire changes in relative abundance of the most common species (the murid rodents Bolomys lasiurus, Calomys callosus, C. tener, Oryzomys subflavus, and Thalpomys cerradensis) for the 1 year following fire. Overall diversity tended to be greater in the protected site both before and after fire. Species composition and diversity indices of the small mammal communities were relatively unaffected by the fires. Thalpomys cerradensis, however, appeared to use only areas that burn frequently and C. callosus showed an immediate post-fire increase in population size in both areas, contrasting with a simultaneous decrease in number of B. lasiurus.

Thalpomys Thomas, endemic to the cerrado of central Brazil, is a strikingly distinct genus of the akodont assemblage (Sigmodontinae, Cricetidae, Rodentia). The genus and the two included species, one new, are described and compared. The validity of the names of the genus and type species T. lasiotis Thomas, 1916, is elucidated. The little known about habitat, relative population numbers, and karyotype is included.

We studied the succession of small mammal species after fire in the cerrado (Neotropical savanna) of Central Brazil. Populations of small mammals were sampled with live-trapping techniques in a series of nine sites of different successional age, ranging from 1 to 26 years after fire. Ten species of small mammals were captured through all the seral stages of succession. Species richness ranged from two to seven species by seral stage. The species were arranged in different groups with respect to abundance along the succession: the first was composed of early successional species that peaked

Thalpomys lasiotis Thomas, 1916. Ann. Mag. Nat. Hist., ser. 8, 18:339. TYPE LOCALITY: Brazil, Minas Gerais, Lagoa Santa. DISTRIBUTION: Cerrado of C Brazil. SYNONYMS: reinhardti. COMMENTS: For synonymy of the replacement name Akodon reinhardti, see Hershkovitz (1990a)., Published as part of Guy G. Musser & Michael D. Carleton, 1993, Order Rodentia - Family Muridae, pp. 501-755 in Mammal Species of the World (2 nd Edition), Washington and London :Smithsonian Institution Press on pages 748-749, DOI: 10.5281/zenodo.7353098, {"references":["Hershkovitz, P. 1990 a. The Brazilian rodent genus Thalpomys (Sigmodontinae, Cricetidae) with a description of a new species. Journal of Natural History, 24: 763 - 783."]}

Thalpomys Thomas, 1916. Ann. Mag. Nat. Hist., ser. 8, 18:339. TYPE SPECIES: Thalpomys lasiotis Thomas, 1916 (not Mus lasiotis of Lund, 1841). COMMENTS: Akodontine. Recognized as a genus, as initially diagnosed, by Gyldenstolpe (1932); reclassified as a subgenus of Akodon by Ellerman (1941) and so observed by Cabrera (1961). See Hershkovitz (1990a) for availability of genus-group name, its differentiating characters from typical Akodon, and definition of included species., Published as part of Guy G. Musser & Michael D. Carleton, 1993, Order Rodentia - Family Muridae, pp. 501-755 in Mammal Species of the World (2 nd Edition), Washington and London :Smithsonian Institution Press on page 748, DOI: 10.5281/zenodo.7353098, {"references":["Lund, P. W. 1841. Blik paa Brasiliens Dyreverden for sidste Jordomvaeltning. Tredie Afhandling: Fortsaettelse af Pattedyrene. Konigelige Danske Videnskabernes Selskabs Afhandlinger, Kjobenhavn, 8: 219 - 272, pls. 14 - 24.","Gyldenstolpe, N. 1932. A manual of Neotropical sigmodont rodents. Kungliga Svenska Vetenskapsakademiens Handlingar, Tredje Serien, 11: 1 - 164.","Ellerman, J. R. 1941. The families and genera of living rodents. Vol. II. Family Muridae. British Museum (Natural History), London, 690 pp.","Hershkovitz, P. 1990 a. The Brazilian rodent genus Thalpomys (Sigmodontinae, Cricetidae) with a description of a new species. Journal of Natural History, 24: 763 - 783."]}

The occurrence and prevalence of Metacuterebra apicalis (Diptera: Cuterebridae) in natural populations of Oryzomys subflavus, Bolomys lasiurus, and Thalpomys cerradensis (Rodentia: Muridae) from August 1990 to July 1992 in the cerrado, a common savanna-like vegetation type of central Brazil, are reported. An increase in bot infection in the 3 rodent species between October 1991 and July 1992 without correlation to precipitation was detected. The prevalence was lower than in neotropical forest formations. Mean intensity was 1.3 bots (range 1-2) for T. cerradensis and 1 bot for B. lasiurus and O. subflavus. This is the first record of T. cerradensis as host of bot flies.