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We present a new assessment of the genetic and morphological variation within Oxymycterus quaestor Thomas, 1903, which currently includes the junior synonyms O. judex Thomas, 1909 and O. misionalis Sanborn, 1931. We integrate distinct lines of evidence, including variation of mitochondrial (Cytochrome b [Cytb]) and nuclear (intron 7 of beta fibrinogen gene [Fgb]) sequences, and the assessment of skull quantitative traits based on geometric morphometrics, throughout the Atlantic Forest of Southeastern-Southern Brazil, Argentina, and Paraguay. Phylogenetic relationships based on Cytb indicate that O. quaestor is structured in four well-supported clades (lineages A–D), one of them (lineage C) including topotypes of a previously associated nominal form (O. judex). However, these Cytb lineages exhibit lower levels of differentiation based on the Fgb locus, and are not recovered in the genealogies of this nuclear marker, representing a case of mitonuclear discordance. The Cytb lineages also broadly overlapped in the morphospace both in skull shape and size, which sustain the current wider concept of O. quaestor as one single young species (0.947 Myr) that is recently expanding, and ultimately branching out, in the Atlantic Forest.

Akodon is the most diverse genus of the tribe Akodontini, comprising 41 extant species. Although distributed in a wide range of environments in South America, the genus was long considered to be absent from Amazon Forest. Nonetheless, in recent decades, records of Akodon have been reported based on specimens from southern Amazonia, throughout the contact zone with Cerrado. Published data about the unique karyotype (2n=10), along with evidence of sister phylogenetic relationship (Cytb sequences) with Akodon cursor, a species from the Atlantic Forest, suggest that these specimens represent an undescribed species. Herein we hypothesize that these samples represent a new species of Akodon from Amazonia-Cerrado transitional areas. Through the analyses of 217 specimens from Mato Grosso and Pará states, Brazil, as well as 336 specimens of Akodon cursor species group from the Atlantic Forest, we provide qualitative and quantitative external and craniodental data that support their distinction in comparison with other congeners. The sister relationship between this new species and A. cursor provide additional evidence of a past connection between the two largest tropical forests of South America. Moreover, the recognition of Akodon n. sp. points to the presence of the genus in the Amazonia-Cerrado transition, an area currently under great anthropic pressure, highlighting the fact that we might be losing a portion of Brazilian biodiversity before even getting to know it.

The genus Brucepattersonius currently includes eight valid species from the Atlantic Forest of south-eastern Brazil and north-eastern Argentina. Most of those species were described in the past 20 years, based on very small sample sizes: four species are known only from their type localities. Concerns on the taxonomic validity of some Brucepattersonius species have been raised in the recent literature. In this study, we present a phylogenetic hypothesis including samples throughout the distribution of the genus (among them the holotypes of two species) and employed single-locus molecular species delimitation analyses to provide a new hypothesis for species limits within Brucepattersonius. We also analysed intra- and interpopulation morphological and morphometric variation to apply an integrative taxonomic approach to species delimitation. Our phylogenetic inference of molecular data recovered four strongly supported clades within Brucepattersonius, which were recognized as distinct operational taxonomic units in all species delimitation analyses. The first two clades represent the Caparaó mountain range endemic B. griserufescens and its sister-group, the recently described species B. nebulosus. The third clade comprises several specimens assigned to B. soricinus but also includes the holotype of B. igniventris; we revise these species limits accordingly. The last clade is composed of samples from southern Brazil assigned to B. iheringi. Based on morphological and morphometric analyses, we find no clear structure among the three described species from Misiones Province, Argentina (B. guarani, B. misionensis and B. paradisus) and B. inheringi from southern Brazil, suggesting that those samples represent a single species. Therefore, in the present study we propose that the genus Brucepattersonius comprises only four diagnosable species: B. griserufescens (including B. albinasus), B. nebulosus, B. soricinus (including B. igniventris) and B. iheringi (including B. guarani, B. misionensis and B. paradisus).

Made available in DSpace on 2021-06-25T10:14:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul The Neotropical region shows a great diversity of fleas, comprising more than 50 genera. The importance of the study of fleas is linked to their potential role as disease vectors. The aim of this study is to investigate the presence of Rickettsia spp. and Bartonella spp. in Neotropical fleas collected from wild rodents in Southern Brazil. From 350 rodents captured, 30 were parasitized by fleas. A total of 61 fleas belonging to two genera and six different species were collected (Craneopsylla minerva minerva, Polygenis occidentalis occidentalis, Polygenis platensis, Polygenis pradoi, Polygenis rimatus, and Polygenis roberti roberti). In 13 % of fleas of three different species (C. minerva, P. platensis, and P. pradoi) Rickettsia sp. DNA was found. Phylogenetic analysis of concatenated sequences of gltA, htrA, and ompA genes showed that Rickettsia sp. found in rodent fleas (referred as strain Taim) grouped together with Spotted Fever Group Rickettsia. In reference to Bartonella spp., five genotypes were identified in seven fleas of two species (C. minerva and P. platensis) and in five rodent spleens. Also, 207 frozen samples of wild rodents were screened for these pathogens: while none was positive for Rickettsia spp.; five rodent spleens were PCR-positive for Bartonella spp. Herein, we show the detection of potential novel variants of Bartonella sp. and Rickettsia sp. in fleas collected of wild rodents from Southern Brazil. Further studies are needed to fully characterize these microorganisms, as well as to improve the knowledge on the potential role of Neotropical flea species as diseases vectors. Centro de Pesquisa em Saúde Animal Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF) Área de Vida Assessoria e Consultoria em Biologia e Meio Ambiente Universidade Luterana do Brasil Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) Museu de Ciências Naturais (MCN) Fundação Zoobotânica do Rio Grande do Sul (FZB-RS) Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP)

Neotropical cricetid rodents of the subfamily Sigmodontinae constitute an incredibly diverse and ubiquitous clade of mammals in South America. In spite of recent advances in sigmodontine systematics, a variable collection of genera from eastern South America with no clear tribal affiliations and well-differentiated morphologies has been pervasive in most classification attempts, being generally listed as Sigmodontinae incertae sedis. Here, we assess the phylogenetic relationships of these incertae sedis genera based on supermatrix and multispecies coalescent analyses of a multilocus molecular dataset (one mitochondrial and five nuclear loci) for 76 genera, calibrated with ten fossil-based node dates. Both analytical approaches provided concordant and unprecedented resolution of suprageneric clades within the large Oryzomyalia clade (constituted by most sigmodontine genera), recovering a natural group constituted by the genera Wiedomys, Wilfredomys, and the Atlantic Forest endemics Juliomys and Phaenomys - here redefined as the Wiedomyini tribe - and a sister-relationship between this group and the tribe Abrotrichini. The enigmatic spiny rodent genus Abrawayaomys was recovered as sister to Akodontini in three of four analyses, but pending higher support. Morphological comparisons performed among the four wiedomyine genera highlighted a number of shared external, cranial, and dental similarities useful to emend the tribe diagnosis, such as the presence of chromo-genetic fields associated with the muzzle, pinnae, and rump, the long and narrow rostrum flanked by shallow and narrow zygomatic notches, and the asymmetrically divided procingulum of M1, among other characters. Molecular dating coupled with fossil evidence suggests Wiedomyini as one of the oldest sigmodontine tribes with a late Miocene autochthonous origin in eastern South America, highlighting the relevance of this region as an ancient cradle of sigmodontine lineages.

Sigmodontinae is a very rich clade of rodents that is widespread throughout the Neotropics. The arboreal mice Juliomys comprise a poorly known branch, with incomplete information about species richness, phylogenetic position, and geographic distribution. Based on a sample from the Atlantic Forest of Southern Brazil, we name and describe a new species for the genus. This new species can be distinguished from others in the genus by its karyotype, morphological traits, and cytochrome b ( Cytb ) gene sequence. It has a unique karyotype (2n = 32, FN = 48), and forms a well-supported monophyletic haplogroup, which is phylogenetically distant from the remaining species of Juliomys . The genetic differentiation ranges from 11.1% to 19.7%, and there are 24 molecular autopomorphies in the Cytb gene. The new species can be distinguished from J . pictipes by morphological and morphometric analyses. However, we consider the new species as cryptic, not easily recognized by morphological characteristics of other species of Juliomys . This taxon seems to be endemic to the Brazilian Araucaria Forest in the Atlantic Forest biome, occurring in sympatry with its congeneric species J. ossitenuis and J. pictipes . In this research, we describe a new species for the genus and extend species distributions in the Atlantic Forest. Sigmodontinae e um clado de roedores muito diverso com especies distribuidas por toda a regiao Neotropical. Dentre esses, as especies de roedores arboricolas inclusos em Juliomys formam um ramo pouco conhecido, com informacoes incompletas sobre a sua riqueza, posicao filogenetica e distribuicao geografica. A partir de uma amostra proveniente da porcao sul do Bioma Mata Atlântica, nomeamos e descrevemos uma nova especie para o genero, a qual pode ser distinguida das demais pelo seu cariotipo, caracteristicas morfologicas e sequencia do gene citocromo b . Essa apresenta um cariotipo unico (2n = 32, FN = 48) e forma um haplogrupo monofiletico com bom suporte, sendo filogeneticamente distante das especies restantes de Juliomys . A diferenciacao genetica dessa especie em relacao as demais varia de 11,1% a 19,7%, possuindo 24 autapomorfias moleculares no gene do citocromo b . A nova especie pode ser distinguida de J . pictipes por caracteres morfologicos e analises morfometricas. No entanto, consideramos a nova especie como criptica, nao facilmente reconhecida, pelos caracteres morfologicos, das demais que compoem Juliomys . Esse novo taxon parece ser endemico da Floresta com Araucaria no Bioma Mata Atlântica, ocorrendo em simpatria com as especies congenericas, J. ossitenuis e J. pictipes . Nesse estudo, descrevemos uma nova especie para o genero, e estendemos a distribuicao das especies na Mata Atlântica.

Geographic distribution is critical information for conservation of the species. In this note we report the southernmost record of Akodon serrensis, a Neotropical terrestrial rodent endemic of the Brazilian Atlantic Forest, but yet with undefined distribution limits.

Machado, L.F., Leite, Y.L.R., Christoff, A.U. & Giugliano, L.G. (2014). Phylogeny and biogeography of tetralophodont rodents of the tribe Oryzomyini (Cricetidae: Sigmodontinae). —Zoologica Scripta, 43, 119–130. Oryzomyini is the richest tribe among the Sigmodontine rodents, encompassing 32 living and extinct genera and including an increasing number of recently described species and genera. Some Oryzomyini are tetralophodont showing a reduction in the number of molar folds to four, while most taxa in this tribe retain the plesiomorphic pentalophodont state. We applied phylogenetic methods, molecular dating techniques and ancestral area analyses to members of an oryzomyini clade informally named ‘D’ in former studies and included related fossil tetralophodont forms. Based on 98 morphological characters and sequences of five gene fragments, we found that the tetralophodont condition is paraphyletic. Among living taxa, Pseudoryzomys is sister to Holochilus, and Lundomys is derived from a basal divergence. A clade formed by living Holochilus and the fossils Noronhomys and Carletonomys is sister to Holochilus primigenus, making Holochilus paraphyletic. Therefore, we describe a new genus that accommodates the fossil H. primigenus. Because trans-Andean taxa currently share a common ancestor with taxa of cis-Adean distribution, the northern Andes uplift may have worked as a postdispersal barrier. The tetralophodont lineages diverged during the Pliocene from a cis-Andean ancestor, and the Great Plains in South America may have favoured the diversification of tetralophodont forms adapted to open habitats during the Pliocene.

Made available in DSpace on 2021-06-25T12:17:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-11-23 Villanova Univ, Dept Biol, Villanova, PA 19085 USA Museu Nacl Hist Nat & Ciencia, Lisbon, Portugal Univ Brasilia, Dept Zool, Inst Ciencias Biol, BR-70910900 Brasilia, DF, Brazil Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA Sorbonne Univ, Museum Natl Hist Nat, ISYEB, Paris, France Univ Nacl Tucuman, San Miguel De Tucuman, Argentina King Saud Univ, Riyadh, Saudi Arabia Cornell Univ, Ithaca, NY USA Univ Fed Sao Paulo, Diadema, Brazil Upper Austrian Museum, Ctr Biol, Linz, Austria Villanova Univ, Villanova, PA 19085 USA Univ Salzburg, Salzburg, Austria Plazi, Bern, Switzerland Univ Brasilia, Brasilia, DF, Brazil Univ Sao Paulo, Ribeirao Preto, Brazil Zool Forsch Museum A Koenig, Bonn, Germany Museu Paraense Emilio Goeldi, Belem, Para, Brazil Russian Acad Sci, St Petersburg, Russia Pontificia Univ Catolica Rio Grande do Sul, Porto Alegre, RS, Brazil Museo Reg Sci Nat, Turin, Italy Univ Fed Rio Grande do Sul, Porto Alegre, RS, Brazil Royal Museum Cent Africa, Tervuren, Belgium Univ Nacl Autonoma Mexico, Mexico City, DF, Mexico Univ Innsbruck, Inst Ecol, Innsbruck, Austria Hasselt Univ, Hasselt, Belgium Univ Fed Pernambuco, Recife, PE, Brazil Univ Fed Espirito Santo, Vitoria, ES, Brazil Univ Nacl Misiones, Felix De Azara, Argentina Albany Museum, Grahamstown, South Africa Natl Museum, Bloemfontein, South Africa Senckenberg Nat Hist Sammlungen, Dresden, Germany Univ Estadual Paulista, Botucatu, SP, Brazil Stephen F Austin State Univ, Nacogdoches, TX 75962 USA Landesmuseum, Leonding, Austria Univ Camerino, Camerino, Italy Univ Fed ABC, Sao Bernardo, Brazil Univ Estadual Londrina, Museu Zool, Londrina, Parana, Brazil Senckenberg Res Inst, Frankfurt, Germany Museo Civ Storia Nat, Carmagnola, Italy Polskiej Akad Nauk, Muzeum & Inst Zool, Warsaw, Poland Museo Civ Storia Nat, Genoa, Italy Russian Acad Sci, Inst Zool, St Petersburg, Russia Univ Estadual Paulista, Sao Vicente, Brazil Sorbonne Univ, ISYEB, Museum Natl Hist Nat, Paris, France Port Elizabeth Museum, Port Elizabeth, South Africa Sam Noble Museum, Norman, OK USA Harvard Univ, Museum Comparat Zool, Cambridge, MA 02138 USA North West Univ, Potchefstroom, South Africa Museu Nacl, Rio De Janeiro, Brazil Nat Hist Museum, Basel, Switzerland Senckenberg Nat Kundemuseum, Gorlitz, Germany North Carolina Museum Nat Sci, Raleigh, NC USA Univ Rennes 1, Rennes, France Univ Sao Paulo, Museu Zool, Sao Paulo, SP, Brazil Amer Museum Nat Hist, New York, NY 10024 USA Univ Huddersfield, Huddersfield, W Yorkshire, England North Dakota State Univ, Fargo, ND USA Univ Sao Paulo, Sao Paulo, SP, Brazil Fac Sci Sfax, Sfax, Tunisia DPTC PC, Manaus, Amazonas, Brazil Louisiana State Univ, Museum Nat Sci, Baton Rouge, LA 70803 USA Zool Survey India, Kolkata, India Univ Tennessee, Chattanooga, TN USA Ohio State Univ, Columbus, OH 43210 USA Univ Luterana Brasil, Museu Ciencias Nat, Canoas, Brazil Univ Firenze, Florence, Italy Univ Ovidius Constanta, Constanta, Romania Univ Mississippi, Oxford, MS USA Royal Belgian Inst Nat Sci, Brussels, Belgium Univ New Mexico, Albuquerque, NM 87131 USA Inst Nacl de Pesquisas da Amazonia, Manaus, Amazonas, Brazil Univ Stellenbosch, Matieland, South Africa Univ Fed Minas Gerais, Belo Horizonte, MG, Brazil CIBIO Ctr Invest Biodiversidade & Recursos Genet, Vairao, Portugal Museum Hist Nat, Geneva, Switzerland Univ Fed Mato Grosso, Cuiaba, Brazil Univ Austral Chile, Valdivia, Chile Univ Malaysia, Sarawak, Malaysia Indian Inst Sci, Bangalore, Karnataka, India Scottish Assoc Marine Sci, Oban, Argyll, Scotland Sam Houston State Univ, Huntsville, TX 77340 USA Museo Nacl Ciencias Nat, Madrid, Spain Sorbonne Univ, CR2P, Museum Natl Hist Nat, Paris, France Drexel Univ, Acad Nat Sci, Philadelphia, PA 19104 USA Univ Richmond, Richmond, VA 23173 USA Ctr Pesquisas Cacau, Itabuna, Brazil Univ Torino, Turin, Italy Soc Hist Nat Alcide dOrbigny, Aubiere, France Wolfden Sci Consulting, Murcia, Spain Univ Fed Rio de Janeiro, Macae, Brazil Univ Tennessee, Knoxville, TN USA Inst Humboldt, Villa De Leyva, Colombia Escuela Politec Nacl, Quito, Ecuador Calif Acad Sci, San Francisco, CA 94118 USA Museum Dept Hist Nat Var, Toulon, France Nat Environm & Wildlife Soc, Angul, India Univ Kansas, Lawrence, KS 66045 USA Kyoto Univ, Kyoto, Japan Consejo Nacl Invest Cient & Tecn, Museo Argentino Ciencias Nat Bernardino Rivadavia, Buenos Aires, DF, Argentina Univ Fed Paraiba, Joao Pessoa, Paraiba, Brazil Univ Fed Parana, Curitiba, Parana, Brazil Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil Nat Hist Museum Narodini Museum, Prague, Czech Republic Nat Hist Museum Zimbabwe, Bulawayo, Zimbabwe Ateneo Manila Univ, Quezon City, Philippines Pontificia Univ Javeriana, Bogota, Colombia RACINE, St Maugan, France Univ Paris 06, Sorbonne Univ Paris, ISYEB, Paris, France Ocean Univ China, Qingdao, Peoples R China Museo Nacl Hist Nat Paraguay, San Lorenzo, Paraguay Univ Carabobo, Valencia, Venezuela Natl Ctr Biol Sci, 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Jr Coll, Santa Rosa, CA USA George Washington Univ, Washington, DC 20037 USA Inst Teknol Bandung, Bandung, Indonesia Earlham Coll, Richmond, IN USA Senckenberg Forschungsinst & Nat Museum, Frankfurt, Germany Univ Estadual Londrina, Londrina, Parana, Brazil Univ Koblenz Landau, Koblenz, Germany Nat Hist Museum, London, England Ditsong Natl Museum Nat Hist, Pretoria, South Africa Bombay Nat Hist Soc, Bombay, Maharashtra, India Philipps Univ Marburg, Marburg, Germany Hess Landesmuseum, Darmstadt, Germany Smithsonian Conservat Biol Inst, Washington, DC USA Univ Pannonia, Keszthely, Hungary Staatliches Museum Nat Kunde, Stuttgart, Germany UFT, Tocantins, Portugal Museum Nat Kunde, Berlin, Germany Nat Hist Riksmuseet, Stockholm, Sweden Hikarigaoka, Munakata, Japan Inst Agr & Environm Sci, Tartu, Estonia Univ Los Andes, Merida, Venezuela Bat Jungle, Monteverde, Costa Rica Texas A&M Univ, College Stn, TX USA Yale Univ, New Haven, CT USA Univ Estadual Paulista, Sao Jose Do Rio Preto, Brazil Museo Nacl Hist Nat, Montevideo, Uruguay Consejo Nacl Invest Cient & Tecn, Fdn Miguel Lillo, San Miguel De Tucuman, Argentina Roger Tory Peterson Inst Nat Hist, Jamestown, VA USA Univ Fed Reconcavo Bahia, Cruz Das Almas, Brazil South China Normal Univ, Guangzhou 510631, Guangdong, Peoples R China Museu Ciencias Tecnol PUCRS, Porto Alegre, RS, Brazil Univ Fed Tocantins, Porto Nacl, Brazil Univ Toronto, Scarborough, ON, Canada Univ Nacl Colombia, Inst Ciencias Nat, Bogota, Colombia Natl Museum Philippines, Manila, Philippines NOVA Univ Lisbon, Caparica, Portugal Royal Saskatchewan Museum, Regina, SK, Canada Deutsch Zentrum Marine Biodiversitatsforsch, Hamburg, Germany Ctr Invest Biol Noroeste, La Paz, Mexico Naturalis Biodivers Ctr, Leiden, Netherlands Univ Douala, Douala, Cameroon Vet & Farmaceut Univ Brno, Brno, Czech Republic Univ Swaziland, Kwaluseni, Eswatini Fundacao Oswaldo Cruz, Rio De Janeiro, Brazil Univ Claude Bernard, Lyon, France Museum Vertebrate Zool, Berkeley, CA USA Smithsonian Inst, Washington, DC 20560 USA Nat Hist Museum & Inst, Chiba, Japan Senckenberg Biodiversitat & Klima Forschunsgzentr, Frankfurt, Germany Marquette Univ, Milwaukee, WI 53233 USA Univ Firenze, Museo Storia Nat, Florence, Italy Univ Fed Bahia, Salvador, BA, Brazil Fed Univ ABC, Sao Bernardo, Brazil Univ Fed Goias, Goiania, Go, Brazil Univ Alaska Museum, Fairbanks, AK USA Egerton Univ, Egerton, Kenya Museo Hist Nat, Lima, Peru IKIAM Univ Reg Amazon, Tena, Ecuador Univ Hyogo, Sanda, Japan Inst Rech Dev, Paris, France Univ Sao Paulo, Piracicaba, Brazil Niedersachs Landesbetrieb Wasserwirtschaft Kusten, Hannover, Germany Univ Complutense Madrid, Madrid, Spain Consejo Nacl Invest Cient & Tecn, Ctr Nacl Patagon, Puerto Madryn, Argentina Roosevelt Univ, Coll Profess Studies, Chicago, IL 60605 USA Western Kentucky Univ, Bowling Green, KY 42101 USA Univ Naples Federico II, Naples, Italy Univ Fed Acre, Rio Branco, Acre, Brazil Univ Fed Santa Catarina, Florianopolis, SC, Brazil Inst Bio & Geociencias Noroeste Argentino, Salta, Argentina Inst Venezolano Invest Cient, Caracas, Venezuela Umweltbundesamt, Vienna, Austria Penclen, Plumelec, France CNRS MNHN UPMC, Ctr Rech Paleobiodivers & Paleoenvironm, Paris, France Staatl Museum Nat Kunde, Stuttgart, Germany Consejo Nacl Invest Cient & Tecn, Museo Argentino Ciencias Nat Bernardino Rivada, Buenos Aires, DF, Argentina Ctr Biol Gest Populat INRA, Montferrier Sur Lez, France Loyola Univ Chicago, Chicago, IL USA Pontificia Univ Catolica Rio do Sul, Porto Alegre, RS, Brazil Durban Museum Nat Sci, Durban, South Africa Univ Estado Amazonas, Manaus, Amazonas, Brazil Brigham Young Univ, Provo, UT 84602 USA Museo Hist Nat La Salle, Caracas, Venezuela Univ Vet Med Hannover, Hannover, Germany Australian Museum, Sydney, NSW, Australia Texas Tech Univ, Lubbock, TX 79409 USA Francis Marion Univ, Florence, SC USA Univ Washington, Seattle, WA 98195 USA Univ Connecticut, Groton, CT USA Fed Univ ABC, Santo Andre, SP, Brazil Univ Fed Uberlandia, Uberlandia, MG, Brazil Fed Univ Para, Belem, Para, Brazil Yale Peabody Museum, New Haven, CT USA Univ Texas Arlington, Arlington, TX 76019 USA Senckenberg Deutsch Entomol Inst, Muncheberg, Germany CSIRO, Natl Res Collect, Canberra, ACT, Australia Univ Venda, Thohoyandou, South Africa Univ Ulsan, Ulsan, South Korea Univ Estadual Sao Paulo, Botucatu, SP, Brazil Senckenberg Forsch Inst & Nat Museum, Frankfurt, Germany Ocean Univ China, Inst Marine Biodivers & Evolut, Qingdao, Shandong, Peoples R China Univ Fed Para, Altamira, Brazil Univ Estadual Paulista, Assis, Brazil UPMC, Ctr Rech Paleobiodiversite & Paleoenvironm, CNRS, MNHN, Paris, France Tech Univ Kaiserslautern, Kaiserslautern, Germany Charles Univ Prague, Dept Zool, Prague, Czech Republic Univ Nacl Expt los Llanos Occident Ezequiel Zamor, Guanare, Venezuela Long Isl Univ, Brooklyn, NY USA Univ Ryukyus, Okinawa, Japan Pontificia Univ Catolica Ecuador, Museo Zool, Escuela Ciencias Biol, Quito, Ecuador Indiana Univ Penn, Indiana, PA USA IRD, Dakar, Senegal State Museum Nat Hist Karlsruhe, Karlsruhe, Germany Univ Toulouse III Paul Sabatier, Toulouse, France Univ Ghent, Ghent, Belgium Univ Antwerp, Antwerp, Belgium Karlsruhe Inst Technol, Karlsruhe, Germany Ctr Cellular & Mol Biol, Hyderabad, India Univ Fed ABC, Santo Andre, Brazil Yale Peabody Museum Nat Hist, New Haven, CT USA Univ Innsbruck, Mondsee, Austria Bethune Cookman Univ, Daytona Beach, FL USA Natl Museum Nat & Sci, Tokyo, Japan Zool Garten Koln, Cologne, Germany Univ Estadual Paulista, Botucatu, SP, Brazil Univ Estadual Paulista, Sao Vicente, Brazil Univ Estadual Paulista, Rio Claro, Brazil Univ Estadual Paulista, Sao Jose Do Rio Preto, Brazil Univ Estadual Paulista, Assis, Brazil

As matas de restinga representam formações vegetais originais na Planície Costeira do estado do Rio Grande do Sul. O objetivo deste trabalho foi avaliar a composição de espécies de pequenos mamíferos não-voadores em dois fragmentos de matas de restinga (mata palustre e mata arenosa ciliar) no município de Rio Grande, região sul da Planície Costeira do Rio Grande do Sul. Um total de 234 indivíduos pertencentes a três espécies de marsupiais (Didelphidae: Cryptonanus guahybae, Didelphis albiventris, Lutreolina crassicaudata) e oito espécies de roedores (Cricetidae: Deltamys kempi, Holochilus brasiliensis, Oligoryzomys flavescens, O. nigripes, Oxymycterus nasutus, Scapteromys tumidus; Muridae: Mus musculus, Rattus rattus) foi capturado. As espécies C. guahybae, D. albiventris, D. kempi, H. brasiliensis, O. nigripes, S. tumidus e M. musculus foram registradas no fragmento de mata palustre, enquanto que C. guahybae, D. albiventris, Lutreolina crassicaudata, D. kempi, O. flavescens, O. nigripes, S. tumidus e R. rattus ocorreram no fragmento de mata arenosa ciliar. Oligoryzomys nigripes e S. tumidus foram as espécies mais abundantes no fragmento de mata palustre, representando respectivamente 40,4 e 22,1% do total de indivíduos capturados. No fragmento de mata arenosa ciliar, as espécies mais abundantes foram O. nigripes e D. albiventris, representando respectivamente 63,4 e 12,4% do total de indivíduos capturados. Indivíduos de C. guahybae e O. nigripes foram capturados em estrato arbóreo(alturas entre 0,50 e 1,65 m) enquanto que todos os indivíduos das demais espécies foram capturados no solo. The restinga forests represent original vegetal formations in Coastal Plain of Rio Grande do Sul state. This work aimed to evaluate the species composition of non-volant small mammals in two restinga forests (peat forest and sandy riparian forest) in Rio Grande, Southern Rio Grande do Sul Coastal Plain. A total of 234 individuals belonging to three species of marsupials (Didelphidae: Cryptonanus guahybae, Didelphis albiventris, Lutreolina crassicaudata) and eight species of rodents (Cricetidae: Deltamys kempi, Holochilus brasiliensis, Oligoryzomys flavescens, O. nigripes, Oxymycterus nasutus, Scapteromys tumidus; Muridae: Mus musculus, Rattus rattus) was captured. The species C. guahybae, D. albiventris, D. kempi, H. brasiliensis, O. nigripes, S. tumidus and M. musculus were recorded in the peat forest while C. guahybae, D. albiventris, Lutreolina crassicaudata, D. kempi, O. flavescens, O. nigripes, S. tumidus and R. rattus occurred in the riparian sandy forest. Oligoryzomys nigripes and S. tumidus were the most abundant species in the peat forest, representing 40.4 and 22.1% of the total of captured individuals, respectively. The most abundant species in the riparian sandy forest were O. nigripes e D. albiventris, representing 63.4 and 12.4% of the total of captured individuals. Individuals of C. guahybae and O. nigripes were captured on trees (heights between 0.50 and 1.65 m) while all individuals of the remaining species were captured on the ground.

A análise dos padrões microscópicos de pelos de mamíferos é uma técnica não-invasiva que pode auxiliar na identificação dos marsupiais brasileiros. O objetivo deste trabalho foi identificar padrões microscópicos dos pelos-guarda (cutícula e medula) de marsupiais ocorrentes no Rio Grande do Sul (RS), propondo uma chave dicotômica para sua identificação a partir dessas estruturas. Além disso, nós apresentamos, com detalhes, os padrões tricológicos de espécimes do gênero Monodelphis, um gênero ainda taxonomicamente obscuro que requer revisão no RS. Obtivemos o material analisado por meio da coleta de pelos de marsupiais capturados em campo ou provenientes de coleções de diferentes instituições. Identificamos os padrões dos pelos de dez espécies de marsupiais: Caluromys lanatus, Chironectes minimus, Didelphis aurita, Didelphis albiventris, Cryptonanus guahybae, Gracilinanus agilis, Gracilinanus microtarsus, Lutreolina crassicaudata, Micoureus paraguayanus e Philander frenatus. Os indivíduos do gênero Monodelphis foram analisados em conjunto, como parte do grupo dimidiata. Encontramos três padrões dentro desse grupo, sugerindo que possa haver uma terceira espécie além das duas normalmente reconhecidas (M. brevicaudis e M. dimidiata). A análise dos padrões microscópicos dos pelos possibilitou a identificação, com sucesso, da grande maioria das espécies à que pertencem os marsupiais do Rio Grande do Sul. Os resultados obtidos sugerem que as duas espécies de Monodelphis grupo dimidiata possam ocorrer com uma distribuição distinta no estado, estando uma presente principalmente na porção norte e a outra na porção leste do RS, com sobreposição na região central. The analysis of mammalian hairs is a non-invasive technique that may help in the identification of Brazilian marsupials. Our objective was to identify microscopic patterns of marsupial guard-hairs (cuticle and medulla) from species with occurrence in the state of Rio Grande do Sul, southern Brazil. We also present a hair-based identification key for this group. Specifically for Monodelphis, a still taxonomically obscure genus that needs revision, we present detailed description of observed hair patterns. We obtained the analyzed material by collecting hair samples of marsupials captured in field or else deposited in different zoological collections. We identified hair patterns of ten marsupial species: Caluromys lanatus, Chironectes minimus, Didelphis aurita, Didelphis albiventris, Cryptonanus guahybae, Gracilinanus agilis, Gracilinanus microtarsus, Lutreolina crassicaudata, Micoureus paraguayanus and Philander frenatus. Individuals of the Monodelphis genus were analyzed together, considered as part of the dimidiata group. We found three distinct patterns for this group, suggesting the possible occurrence of a third species besides the two already recognized (M. brevicaudis and M. dimidiata). These morphs show distinct distribution in the state, with some degree of distribution overlap. The analysis of microscopic patterns of mammal hairs allowed the successful identification of the great majority of marsupials that occur in the Rio Grande do Sul state. Our results suggest that the two Monodelphis species of the dimidiata group might occur with a distinct distribution in the state, one of them occupying mainly the northern part and the other one the eastern region, with some overlap in the central part of the state.

Deltamys Thomas 1917 is a poorly studied and rarely collected taxon of Akodontini (Sigmodontinae). The single described species, Deltamys kempi (DKE), has a basic karyotype with a diploid number of 2n = 37 in males and 2n = 38 in females, a fundamental number FN = 38 for both sexes, and an X1X1X2X2/X1X2Y sex determination system. Herein, a new allopatric form, Deltamys sp. (DSP), is reported, based on specimens from southern Brazil, with 2n = 40, FN = 40 and XX/XY sex chromosomes. We describe the karyotype and mechanism of chromosomal differentiation between both Deltamys complements. Phylogenetic analyses, based on the complete sequence (1,140 bp) of the mitochondrial cytochrome b gene, grouped Deltamys sp. as sister species to D. kempi, with up to 12% genetic divergence between them. The GTG-banding patterns show complete autosomal correspondence between D. kempi and Deltamys sp. and identify a tandem rearrangement involving DSP7, DSP19 and DKE4 that is responsible for the differences in 2n and FN. Chromosome painting with Akodon paranaensis chromosome 21 (a small metacentric akodont marker) paint revealed total homology with the smallest acrocentric Deltamys sp. chromosome, DSP19. This suggests the occurrence of a pericentric inversion or centromeric shift when compared to other akodontines, with a posterior tandem rearrangement giving rise to DKE4. In DKE, large blocks of pericentromeric constitutive heterochromatin are present on the autosomes and the X, and the Y/autosome has an entirely heterochromatic short arm. In DSP, small heterochromatic blocks are observed on autosomes and X, and the Y is a very small, mostly heterochromatic acrocentric. The cytogenetic analyses suggest that the Deltamys sp. karyotype is ancestral, with the derived condition resulting from a tandem fusion (DSP7 + DSP19) and the Y/autosome translocation giving rise to the multiple sex chromosome system. The autosomal rearrangements, the differences in CBG-banding patterns and Ag-NOR localization, as well as the presence of X1X1X2X2/X1X2Y and XX/XY sex determination mechanisms, possibly acting as a reproductive barrier, and the phylogenetic position within the Deltamys genus, with high genetic divergence, call for a taxonomic review of the genus.

EnglishThe present work reports the ecosystems of occurrence of wild boars and feral pigs (Sus scrofa) in the Restinga of Rio Grande, Southern Lagunar Plain of Rio Grande do Sul State, besides showing preliminary data on environmental impacts. Between November 2006 and February 2009 the presence of S. scrofa was recorded in the following ecosystems: restinga woods (peat wood and sandy riparian wood), salt marsh, coastal dune formations, and oceanic beach. In relation to the phenotypical types, wild boars were found within both wood formations, while feral pigs were sighted within and around the borders of the peat wood. It was not possible to determine the occurring phenotypical types in the salt marsh and coastal dunes, since the presence of S. scrofa in these environments was recorded through the identification of footprints, feces and rooting. The largest rooted area was found in the salt marsh with 49 meter length. The removal of the gramineous and herbaceous vegetation, and seedlings and saplings of arboreal species was verified in rooted areas. Seeds of Syagrus romanzoffiana were identified in fecal samples within the peat wood. These are the first records of wild boars in coastal restinga environments. These accounts include the city of Rio Grande in the list of cities with confirmed occurrence of the species living in the wild, currently amounting to 32 localities. portuguesO presente trabalho reporta os ecossistemas de ocorrencia de javalis e porcos asselvajados (Sus scrofa) na Restinga de Rio Grande, regiao sul da Planicie Lagunar do Rio Grande do Sul, alem de trazer observacoes preliminares sobre impactos ambientais. Entre novembro de 2006 e fevereiro de 2009, foi registrada a presenca de S. scrofa nos seguintes ecossistemas: matas de restinga (mata paludosa e mata arenosa ciliar), pântano salobro, cordao de dunas costeiras e praia oceânica. Em relacao aos tipos fenotipicos, javalis foram observados no interior de ambos os fragmentos florestais, enquanto porcos domesticos foram encontrados no interior e na borda da mata palustre. Nao foi possivel determinar o fenotipo de ocorrencia no cordao de dunas costeiras e no pântano salobro, mas a presenca de S. scrofa nesses ambientes foi registrada atraves da identificacao de pegadas, fezes e escavacoes. A maior area escavada foi localizada no pântano salobro, apresentando 49m de extensao. Foi verificada a remocao da vegetacao graminea e herbacea e de plântulas e plantas jovens de especies arboreas nas areas acometidas por escavacoes. Sementes de Syagrus romanzoffiana foram identificadas em amostras de fezes no interior da mata palustre. Estes representam os primeiros registros de javalis asselvajados nos ambientes de restingas costeiras do Estado, incluindo o municipio de Rio Grande na relacao dos municipios rio-grandenses com ocorrencia confirmada da especie em vida livre, que ate o momento somam 32 localidades.

Este trabalho contribui com o conhecimento sobre a diversidade da mastofauna ocorrente ao longo dos agroecossistemas constituintes da Bacia hidrográfica do rio da Várzea, Rio Grande do Sul, Brasil. Foram utilizadas diferentes técnicas de amostragem, que possibilitaram confirmar a ocorrência de 46 espécies de mamíferos. Nove espécies estão citadas em pelo menos uma das três listas vermelhas utilizadas como referência nos âmbitos estadual, nacional e mundial. Somando os resultados obtidos neste estudo com os dados disponíveis, principalmente para as unidades de conservação locais, obtemos um total de 85 espécies registradas para a bacia. Esta riqueza representa cerca de 50% dos mamíferos já documentados para o Rio Grande do Sul. Os resultados sugerem a importância da manutenção de Unidades de Conservação em regiões alteradas, atestando a relevância de inventários de fauna local como abordagem inicial a estudos que envolvam distribuição, sistemática, citogenética, fisiologia, ecologia de populações ou comunidades.

Juliomys is a small rodent from the family Cricetidae which inhabits the Atlantic forest and forests from Argentina to eastern Brazil. The three species recognized so far have different karyotypes. In this paper, we describe a new karyotype with 2n = 32, FN = 48 found in Juliomys specimens from a high-altitude area in the Atlantic forest of southern Brazil. The karyotype was analyzed after G- and C-banding and silver staining of the nucleolus organizer regions (Ag-NOR) and its G-banding patterns were compared with those of the newly described species Juliomys ossitenuis (2n = 20, FN = 36). The 2n = 32 karyomorph presented peculiar features and was very different from those of the other species of the genus: J. pictipes (2n = 36, FN = 34), J. rimofrons (2n = 20, FN = 34) and J. ossitenuis (2n = 20, FN = 36). Differences were mostly due to centric and tandem fusions, pericentric inversion and loss of heterochromatin. The karyotype represents a powerful tool to differentiate Juliomys species and our data suggest that the karyotype described herein belongs to a new species.

Phyllomys is the most diverse genus of the subfamily Echimyinae, and is represented by 12 described species endemic to the Atlantic forest of eastern South America. We name and describe a new species of Phyllomys based on specimens collected in southern Brazil. This species is closely related to P. dasythrix and has been referred to as ‘‘Phyllomys aff. dasythrix’’ in the literature. Chromosomal restructuring was probably involved in their speciation because genetic and morphological similarities of the 2 contrast with their karyotypic distinctiveness. The new species of Phyllomys is diagnosed by a unique combination of external, cranial, and karyotypic characters. We propose the conservation status of ‘‘Least Concern’’ for Phyllomys sp. nov., but ‘‘Vulnerable’’ for P. dasythrix. We present an identification key to the living species of Phyllomys.

Wild felids are thought to share parasites with domestic cats. However, little is known of the coccidian parasites of wild felids. We investigated the presence of Sarcocystis spp. in tissues of 6 species of 90 Neotropical small felids killed in road accidents in the state of Rio Grande do Sul, Brazil by using microscopic and molecular techniques. Formalin-fixed tissues from 28 felids were examined, and Sarcocystis felis-like sarcocysts were detected in 4 wild cats (2 Puma yagouaroundi and 2 Leopardus guttulus). By transmission electron microscopy, sarcocysts from a P. yagouaroundi were identical to S. felis from domestic cats in the USA. Direct sequencing of PCR amplicons resulted the unambiguous sequences of the ITS-1 region from 18 of the 31 PCR positive wild cats; 5 sequences from each P. yagouaroundi, and Leopardus geoffroyi, 4 sequences from L. guttulus, and 2 sequences from each Leopardus wiedii, and Leopardus colocolo. Sequences analysis of ITS-1 region revealed the highest identiy (97–99%) with that of previously describe isolates of S. felis from domestic cats in the USA and identified them as S. felis. Tissues of 1 Leopardus pardalis tested by PCR and histology were negative. The phylogenetic relationship indicated that S. felis is quite different to species which employ opossums as their definitive host. This is the first report of S. felis infection in small wild felids from Brazil.

Between 2000 and 2010, digestive tracts collected from carnivore carcasses found in southern Brazil were analyzed to determine the frequency and proportion of items constituting the diets of each species. Material was collected and analyzed from 194 animals of 10 species

The small didelphid marsupial Cryptonanus guahybae was described as a subspecies of Gracilinanus microtarsus and was so far considered endemic to the state of Rio Grande do Sul, southern Brazil. We used morphological data to identify Cryptonanus specimens from the states of Santa Catarina and Parana, deposited in two Brazilian mammal collections. The cytochrome b sequences of our samples formed a well-supported monophyletic group with low intraspecific genetic divergence. This clade showed high interspecific genetic divergence regarding sequences of the two other species of Cryptonanus that occur in Brazil, C. agricolai and C. chacoensis. Diagnostic morphological characters, such as reddish brown dorsal fur, mammary count (7-1-7=15), small molars, and the presence of a complete anterior cingulum on M3, confirm the identification of 20 specimens from southern Brazil as C. guahybae. Considering the morphological diagnoses and the monophyletic and divergent condition of the cytochrome b sequences, it is suitable that these represent the first molecular data for the species. Our results allowed the expansion of the known distribution of C. guahybae throughout the Atlantic Forest phytophysiognomies of the states of Santa Catarina and Parana.

Wilfredomys, a monotypic genus of endangered sigmodontine rats, was historically related to the tribe Thomasomyini or considered "incertae sedis". Given no molecular data is available for Wilfredomys, the phylogenetic position of this taxon is uncertain in relation to modern, molecular hypotheses of sigmodontine relationships. We investigate the phylogeny of Wilfredomys to provide a hypothesis of its position within Sigmodontinae based on nuclear and mitochondrial DNA sequences. Bayesian and maximum likelihood phylogenetic analyses recovered Wilfredomys oenax as sister to Wiedomys pyrrhorhinos, and Wie. cerradensis fell out sister to this clade. At the genus level, Phaenomys is sister to Wilfredomys + Wiedomys, forming a novel and well-supported sigmodontine clade. Our results suggest that tribe Wiedomyini should encompass Wilfredomys in addition to Wiedomys and Cholomys, thus the hypothesis that Wiedomys is paraphyletic should be investigated further. Another plausible classification scheme consistent with our results would be to expand Wiedomyini to encompass the clade composed of Phaenomys + Wilfredomys + Wiedomys. Last, our recovery of an "Atlantic clade" composed of lineages restricted to eastern South America supports the idea that this region has likely played an important role in sigmodontine diversification.

Comparative studies among four species – Akodonazarae (2n = 38), A. lindberghi (2n = 42), A. paranaensis (2n = 44) and A. serrensis (2n = 46) – employing classic cytogenetics (C- and G-bands) and fluorescence in situ hybridization with telomeric (TTAGGG)n sequencesare reported here. Non-telomeric signals in addition to the regular telomeric sites were detected in three species:A. azarae, A. lindberghi and A. serrensis. One interstitial telomeric site (ITS) was observed proximally at the long arm of chromosome 1 of A. azarae. The comparison of G-banding patterns among the species indicated that the ITS was due to a tandem fusion/fission rearrangement. Non-telomeric signals of A. lindberghi and A. serrensis were not related to chromosomal rearrangements; instead, the sequences co-localized with (i) heterochromatic regions of all chromosomes in A. serrensis; (ii) some heterochromatic regions in A. lindberghi, and (iii) both euchromatic and heterochromatic regions in the metacentric pair of A. lindberghi. These exceptional findings revealed that ITS in Akodon can be related to chromosomal rearrangements and repetitive sequences in the constitutive heterochromatin and that the richness of TTAGGG-like sequences in the euchromatin could be hypothesized to be a result of amplification of the referred sequence along the chromosome arms.

This is the first time the karyotype of the Brazilian squirrel Sciurus aestuans ingrami, with 2n = 40, is described. The karyotype of this species comprises 18 pairs of biarmed and one minute pair of acrocentric autosomes, a medium-sized submetacentric X and a medium-sized acrocentric Y. Four pairs have an interstitial secondary constriction, co-located with nucleolar organizer regions (NORs), identified by silver-staining technique and fluorescent in situ hybridization (FISH) with ribosomal 18S/28S probes. The occurrence of multiple interstitial NORs is rare in rodents, and this is one of the few examples, identified by a molecular cytogenetics approach.

This paper presents seven new records of occurrence of Molossus rufus for the state of Rio Grande do Sul, Brazil, three from the Atlantic Forest Biome and four from the Pampa Biome. The southern limit of the known geographical distribution of this species in Brazil is extended by 159 km.

Among the 251 described species of ticks from the genus Ixodes, only eight were previously reported in Brazil, Ixodes amarali, Ixodes aragaoi, Ixodes auritulus, Ixodes fuscipes, Ixodes loricatus, Ixodes luciae, Ixodes paranaensis and Ixodes schulzei. Of those species, I. loricatus is considered commonly found, whereas I. auritulus and I. aragaoi were registered just one time in Rio Grande do Sul (RS) state, Southern Brazil. This paper aims to update the Ixodes species occurring in RS through the investigation of the ixodofauna of small rodents. Data from 314 wild rodents were analyzed from nine municipalities of Pampa biome and five from the Atlantic Rainforest in RS. Rodents belonging to the following species were infested by Ixodes spp. ticks: Akodon azarae, Akodon montensis, Akodon paranaensis, Akodon reigi, Calomys laucha, Delomys dorsalis, Deltamys kempi, Holochilus brasiliensis, Oligoryzomys flavescens, Oligoryzomys nigripes, Oxymycterus nasutus, Scapteromys tumidus (Cricetidae) and Cavia aperea (Caviidae). The tick identification was performed based on morphological dichotomous keys, their updates and by molecular techniques. Considering the ticks from the rodents and those collected directly from the environment, 34 specimens of Ixodes spp. were collected. Our results improved to five the list of Ixodes species that occur in RS: I. loricatus, I. auritulus, I. aragaoi, I. fuscipes and I. longiscutatus. Moreover, the finding of I. longiscutatus increases to nine the number of Ixodes species in Brazil. The occurrence of two species of the Ixodes ricinus complex (I. aragaoi and I. fuscipes) highlights the potential impact of Ixodes spp. ticks on public health.

Cranial and external morphology of 54 specimens of rodents of the genus Akodon from southern Brazil was analyzed. The sample included 27 individuals with a karyotype of 2n = 44 and 13 with 2n = 46 and 14 nonkaryotyped animals. Principal components analysis separated individuals with 2n = 44 from those with 2n = 46. Individuals with 2n = 44 were distinguished from those with 2n = 46 by narrow and elongated molars, ectolophid present, narrow interorbital breadth, reduced tegmen tympani, and distal baculum with the central and lateral digit approximately equal in size and proportions, not enlarged in the extremity. Discriminant functions analyses including 6 A. sanctipaulensis individuals and holotypes of A. serrensis and A. s. leucogula resulted in 3 distinct groups. The 2n = 46 individuals were related to A. serrensis, but those with 2n = 44 were not assignable to any described species for Akodon. We describe and propose the recognition of a new species for the genus.

In a Brazilian population of the neotropical rodent Akodon montensis we found five sex-reversed XY females. These animals were cytogenetically analyzed by chromosome painting using species-specific DNA probes from the Y chromosome, generated by chromosomal microdissection and subsequent use of the degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR). The results showed a chromosome complement with an apparently normal Y chromosome and an X chromosome carrying a translocation that encompasses a large portion of the Y chromosome (seemingly the entire Y). Ovarian histology suggested that these females are fertile. Amplification of the SRY HMG box sequence by PCR shows that at least one copy of the Sry gene is present in the A. montensis XY females. Based on our findings, we suggest that the breakpoint of the X;Y translocation probably altered an X-linked sex-determining locus (or loci), blocking testicular organogenesis in the XY females. Further studies are necessary to determine the precise location and role of this putative sex-determining chromosomal region. Genetic mechanisms of XY sex reversal in A. montensis populations are discussed.

As matas de restinga representam formações vegetais originais na Planície Costeira do estado do Rio Grande do Sul. O objetivo deste trabalho foi avaliar a composição de espécies de pequenos mamíferos não-voadores em dois fragmentos de matas de restinga (mata palustre e mata arenosa ciliar) no município de Rio Grande, região sul da Planície Costeira do Rio Grande do Sul. Um total de 234 indivíduos pertencentes a três espécies de marsupiais (Didelphidae: Cryptonanus guahybae, Didelphis albiventris, Lutreolina crassicaudata) e oito espécies de roedores (Cricetidae: Deltamys kempi, Holochilus brasiliensis, Oligoryzomys flavescens, O. nigripes, Oxymycterus nasutus, Scapteromys tumidus; Muridae: Mus musculus, Rattus rattus) foi capturado. As espécies C. guahybae, D. albiventris, D. kempi, H. brasiliensis, O. nigripes, S. tumidus e M. musculus foram registradas no fragmento de mata palustre, enquanto que C. guahybae, D. albiventris, Lutreolina crassicaudata, D. kempi, O. flavescens, O. nigripes, S. tumidus e R. rattus ocorreram no fragmento de mata arenosa ciliar. Oligoryzomys nigripes e S. tumidus foram as espécies mais abundantes no fragmento de mata palustre, representando respectivamente 40,4 e 22,1% do total de indivíduos capturados. No fragmento de mata arenosa ciliar, as espécies mais abundantes foram O. nigripes e D. albiventris, representando respectivamente 63,4 e 12,4% do total de indivíduos capturados. Indivíduos de C. guahybae e O. nigripes foram capturados em estrato arbóreo (alturas entre 0,50 e 1,65 m) enquanto que todos os indivíduos das demais espécies foram capturados no solo. The restinga forests represent original vegetal formations in Coastal Plain of Rio Grande do Sul state. This work aimed to evaluate the species composition of non-volant small mammals in two restinga forests (peat forest and sandy riparian forest) in Rio Grande, Southern Rio Grande do Sul Coastal Plain. A total of 234 individuals belonging to three species of marsupials (Didelphidae: Cryptonanus guahybae, Didelphis albiventris, Lutreolina crassicaudata) and eight species of rodents (Cricetidae: Deltamys kempi, Holochilus brasiliensis, Oligoryzomys flavescens, O. nigripes, Oxymycterus nasutus, Scapteromys tumidus; Muridae: Mus musculus, Rattus rattus) was captured. The species C. guahybae, D. albiventris, D. kempi, H. brasiliensis, O. nigripes, S. tumidus and M. musculus were recorded in the peat forest while C. guahybae, D. albiventris, Lutreolina crassicaudata, D. kempi, O. flavescens, O. nigripes, S. tumidus and R. rattus occurred in the riparian sandy forest. Oligoryzomys nigripes and S. tumidus were the most abundant species in the peat forest, representing 40.4 and 22.1% of the total of captured individuals, respectively. The most abundant species in the riparian sandy forest were O. nigripes e D. albiventris, representing 63.4 and 12.4% of the total of captured individuals. Individuals of C. guahybae and O. nigripes were captured on trees (heights between 0.50 and 1.65 m) while all individuals of the remaining species were captured on the ground.

Feeding habits of the Molina's hog-nosed skunk, Conepatus chinga (Molina, 1782) in the extreme south of Brazil. We analyzed 60 stomachs of road-kills of C. chinga in the extreme south of Brazil. The contents revealed 808 prey parts, including invertebrates (frequency of occurrence - FO = 96.7% and relative abundance - RA = 94.7%), vertebrates (FO = 18.3% and RA = 2.8%) and plants (FO = 31.7% and RA = 2.3%). We identified 18 kinds of food, including the invertebrate order Coleoptera which showed the highest FO (86.7%) and RA (75.2%). Other important orders were Orthoptera (FO = 35% and RA = 10.4%) and Araneae (FO = 41.7% and RA = 4%). The combination of occurrence and abundance of the preys consumed allowed classifying C. chinga as an omnivorous with a predominance of insects, especially Coleoptera, consuming other invertebrates, vertebrates and plants in smaller numbers. Behavioral and morphological adaptations of C. chinga favor the predation of insects, which are preys that offer low physical resistance and are available in all terrestrial environments.

Oligoryzoms flavescens and O. nigripes are widely distributed and sympatryc in many biomes. The diagnostic characters used to recognize these are not clearly established. In this study description and comparison was conducted of external morphology, anatomy of the skull, teeth, postcranial skeleton, as well as stomach and penis morphology. Statistical analysis was generated from morphometric data. The sample consisted of 208 specimens from 24 localities in Brazil. O. nigripes was found to be larger, with dorsal pelage darker and ventral pelage whitish with black specks, the skull being larger and more robust than O. flavescens. O. flavescens is smaller, with slightly clearer dorsal pelage and yellowish belly. The pattern of cephalic circulation is derived from the second type in both species. Comparison of postcranial skeleton reveals prominent accidents in scapula and humerus in O. flavescens. On the other hand O. nigripes demonstrated numerous differences localized in the iliac blade, orientation of the ischium and prominent accidents in tibia and fibula. The stomach morphology of both taxa had the same unilocular-hemiglandular pattern. The penis consisted of distal baculum tri-digited. Analysis of the discriminant function clearly indicates the distinction of two homogeneous groups represented by the species. According to t test, two morphometric variables (width of the zigomatic plate and width of first upper molar)are irrelevant (P >; 0.05) to the discrimination of taxa. Sexual dimorphism based on morphometry was supported by t test for O. nigripes. In O. flavescens this condition was not supported. Oligoryzomys nigripes e O. flavescens são amplamente distribuídos e simpátricos em diversos biomas. Os caracteres diagnósticos para seus reconhecimentos não são claramente estabelecidos. Neste estudo, foram realizadas a descrição e comparação da morfologia externa, anatomia do crânio, dentes, esqueleto pós crânio, morfologia estomacal e peniana. Análises estatísticas foram geradas a partir de dados morfométricos. A amostra consiste de 208 exemplares provenientes de 24 localidades do Brasil. O. nigripes é maior, com pelagem dorsal mais escura e pelagem ventral esbranquiçada e salpicada de preto. Crânio maior e mais robusto que O. flavescens. O. flavescens é menor, com pelagem dorsal levemente mais clara e ventre amarelado. O padrão de circulação cefálica das duas espécies é derivada de segundo tipo. Em O. flavescens são visualizados acidentes proeminentes na escápula e úmero, enquanto O. nigripes demonstrou maiores diferenças localizadas na crista íliaca, orientação do ísquio e acidentes proeminentes na tíbia e fíbula. A morfologia estomacal de ambos os táxons possui padrão Unilocular-hemiglandular. A morfologia do pênis consiste de báculo central tri-digitado. A análise de função discriminante reconhecem claramente a distinção de dois grupos homogêneos representados pelas espécies. Segundo o teste t duas variáveis morfométricas (largura da placa zigomática e largura do primeiro molar superior) não são relevantes (P >; 0.05) para a discriminação dos táxons. Dimorfismo sexual baseado na morfometria foi sustentado pelo teste t para O. nigripes. Em O. flavescens esta condição não é estatisticamente verificada.

Wilfredomys, a monotypic genus of endangered sigmodontine rats, was historically related to the tribe Thomasomyini or considered "incertae sedis". Given no molecular data is available for Wilfredomys, the phylogenetic position of this taxon is uncertain in relation to modern, molecular hypotheses of sigmodontine relationships. We investigate the phylogeny of Wilfredomys to provide a hypothesis of its position within Sigmodontinae based on nuclear and mitochondrial DNA sequences. Bayesian and maximum likelihood phylogenetic analyses recovered Wilfredomys oenax as sister to Wiedomys pyrrhorhinos, and Wie. cerradensis fell out sister to this clade. At the genus level, Phaenomys is sister to Wilfredomys + Wiedomys, forming a novel and well-supported sigmodontine clade. Our results suggest that tribe Wiedomyini should encompass Wilfredomys in addition to Wiedomys and Cholomys, thus the hypothesis that Wiedomys is paraphyletic should be investigated further. Another plausible classification scheme consistent with our results would be to expand Wiedomyini to encompass the clade composed of Phaenomys + Wilfredomys + Wiedomys. Last, our recovery of an "Atlantic clade" composed of lineages restricted to eastern South America supports the idea that this region has likely played an important role in sigmodontine diversification.

The crab-eating fox, Cerdocyon thous (Linnaeus, 1766), is a small canid with twilight and nocturnal habits from savannas and forests of South America. In this study, we seasonally determined and quantified the diet of C. thous in Lami Biological Reserve, a conservation unit with 179.78ha situated in a suburban area in the municipality of Porto Alegre, southern Brazil. During the year 2000, we collected 80 fecal samples - 20 for each season - in two or three week sampling intervals, along trails inside the Reserve. Samples were dried in an oven for 24h at 60ºC, immersed in 70% alcohol, and prey items were identified using a stereomicroscope. The diet of the crab-eating fox was essentially carnivorous (87.62% composed by vertebrates), with seasonal variation (p = 0.0009) and absence of fruits. Small non-flying mammals and birds were the most frequent prey, being proportionally more preyed in autumn and summer, respectively. Arthropods were more preyed in winter and spring and bird/reptile eggs only in summer and spring, in the reproduction period of these groups. O graxaim-do-mato, Cerdocyon thous (Linnaeus, 1766), é um canídeo de pequeno porte de hábito crepuscular e noturno que ocorre nas savanas e florestas da América do Sul. Neste estudo foi avaliada a sazonalidade e a dieta de C. thous na Reserva Biológica do Lami, uma unidade de conservação com 179,78ha, situada na região suburbana do município de Porto Alegre, no sul do Brasil. Durante o ano de 2000 foram coletadas 80 amostras fecais - 20 por estação do ano - em coletas realizadas a cada duas ou três semanas, percorrendo as trilhas existentes na Reserva. As amostras foram desidratadas em estufa por 24h a 60ºC, imersas em álcool a 70%, e as presas foram identificadas com auxílio de estereomicroscópio. A dieta do graxaim-do-mato apresentou-se essencialmente carnívora (87,62% composta por vertebrados), com variação sazonal (p = 0,0009) e ausência de frutos. Pequenos mamíferos não-voadores e aves foram os itens mais freqüentes, sendo proporcionalmente mais predados no outono e no verão, respectivamente. Artrópodos foram mais predados no inverno e na primavera e ovos de aves e/ou répteis somente no verão e na primavera, período de reprodução nestes dois grupos.

All available published cytogenetic data show the presence of 28 different karyotypes in 311 specimens of A. cursor as an exceptional example of high karyotype variability in a single species. Our present sample of 116 animals collected in the rain forest of the Atlantic coast of the states of Sao Paulo and Bahia, Brazil, show 25 karyotype constitutions. The diploid number (2n) ranged from 16 to 14, and the number of autosomal arms (NF) from 26 to 18, because of centric fusion and pericentric inversions involving two autosome pairs, pericentric inversions in three other chromosome pairs, trisomy in the pair 7 and the presence of two XO females. Synaptonemal complex analysis, associated with data from experimental cross-breeding, suggested that heterozygous individuals for pericentric inversions have normal fertility. In this paper, we have reviewed the chromosomal data of this species, and have thus standardized the karyotype description and chromosome numbering. We discuss about karyotype evolution of Akodon cursor based on the frequency and constitution of karyotypes of all different geographical samples described so far in the literature.

Current patterns of faunal diversity, geographic distribution, phylogenetic relationships and biogeography constitute a tool for understanding the evolutionary history of taxa. The boundaries of these taxa and their phylogenetic relationships reveal speciation events and therefore allow us to raise general hypotheses about the diversification of a particular group. Into the Oryzomyini, one of the most diverse tribe of Sigmodontinae subfamily, we can found the genus Hylaeamys. Currently seven species were described to that genus: H. acritus, H. seuanezi, H. megacephalus, H. oniscus, H. perenensis, H. tatei and H. yunganus. These species are distributed throughout the tropical and subtropical evergreen cis-andinean forests, from sea level to an altitude of 1500 meters, from Venezuela and Guyana, through the Amazon and the Atlantic Forest, to the north of Paraguay. The distribution of taxa within the genus were confusing and phylogenetic relationships among these species have been little explored, as well as the positioning of the genus within the clade B of Oryzomyini tribe and consequently his sister group. So my proposal was to reassess the species currently described through morphometric and molecular data to better explore the diversity within the genus, and the relations within the genus Hylaeamys and clade where it is inserted. My results showed a greater diversity than the currently described. Morphometric analysis could be helpful in the delimitation of taxa, however did not translate all the phylogenetic diversity found within the genus, witch may present cryptic species. The genus is monophiletic and a new species of Hylaeamys related to H. yunganus populations, from eastern South America was recognized. The results, also highlighted a geographical structure present within H. megacephalus, so, samples from north of the Rio Amazonas showed to be genetically distinct to those samples in southern of Rio Amazon. But this pattern was not observed in morphometric analysis. The species of the Atlantic Forest were closer to the western amazonian species. Hylaeamys showed as a sister group of a clade containing Cis and Trans Andean genera: Oecomys, Euryoryzomys and Transandinomys, indicating that the dispersion for trans-Andean areas occurred after the diversification of the Forest clade in South America. Padrões faunísticos atuais de diversidade, distribuição geográfica, relações filogenéticas e biogeográficas constituem uma ferramenta para a compreensão da história evolutiva dos táxons. As delimitações destes táxons e suas respectivas relações filogenéticas nos revelam eventos de especiação e consequentemente nos permitem levantar hipóteses gerais de diversificação de um determinado grupo. O gênero Hylaeamys está inserido na tribo Oryzomyini, a mais diversa da subfamília Sigmodontinae. Possui atualmente sete espécies descritas: H. acritus, H. laticeps, H. megacephalus, H. oniscus, H. perenensis, H. tatei, e H. yunganus. Estas espécies se distribuem pelas florestas tropicais e subtropicais sempre verdes cisandinas, do nível do mar até uma altitude de 1500 metros, desde a Venezuela e as Guianas, passando pela Amazônia e pela Floresta Atlântica, até o norte do Paraguai. A distribuição dos táxons dentro do gênero eram confusas e as relações filogenéticas entre estas espécies, também, foram pouco exploradas, assim como o posicionamento do gênero dentro do clado B da tribo Oryzomyini e consequentemente seu grupo irmão. Portanto, minha proposta foi reavaliar as espécies atualmente descritas abordando de forma integrativa os dados morfométricos e moleculares para melhor explorar a diversidade dentro do gênero, assim como as relações de parentesco dentro do gênero Hylaeamys e do clado onde este se encontra inserido. Como resultado, obtive uma diversidade maior do que a descrita atualmente. Análises morfométricas puderam auxiliar na delimitação dos taxa, porem não traduziu toda a diversidade filogenética encontrada dentro do gênero, podendo o gênero apresentar espécies cripticas. O gênero se mostrou monofilético e uma nova espécie de Hylaeamys, relacionada às populações de H. yunganus do leste da América do Sul foi reconhecida, assim como, ficou evidente a estruturação geográfica presente dentro da espécie H. megacephalus, onde as amostras ao norte do Rio Amazonas se mostraram geneticamente distintas das amostras ao sol do Rio Amazonas. Porém nas análises morfométricas não foi observado esse padrão. As espécies da Floresta Atlântica se mostraram filogeneticamente mais próximas das espécies do oeste Amazônico. Hylaeamys se mostrou groupo irmão de um clado contendo gêneros Cis e Trans- Andinos, sendo eles, Oecomys, Euryoryzomys e Transandinomys, indicando que a dispersão para áreas trans-andinas se deu após a diversificação do gênero na América do Sul.