- Open Access
The phylogenetic position of the enigmatic Atlantic forest-endemic spiny mouse Abrawayaomys (Rodentia: Sigmodontinae)
© Ventura et al.; licensee Springer. 2013
- Received: 18 February 2013
- Accepted: 30 October 2013
- Published: 9 December 2013
The phylogenetic position of the sigmodontine genus Abrawayaomys, historically assigned to the tribe Thomasomyini or considered a sigmodontine incertae sedis, was assessed on the basis of nuclear and mitochondrial DNA sequences obtained from four individuals from different localities in the Atlantic forest of Brazil. Sequences of Abrawayaomys were analyzed in the context of broad taxonomic matrices by means of maximum-likelihood (ML) and Bayesian analyses (BA).
The phylogenetic position of Abrawayaomys differed depending on the gene analyzed and the analysis performed (interphotoreceptor retinoid-binding protein (IRBP) ML: sister to Thomasomyini; IRBP BA: sister to Akodontini; cytochrome (Cyt) b ML: sister to Neotomys; and Cyt b BA: sister to Reithrodontini). With the sole exception of the BA based on Cyt b sequences, where the Abrawayaomys-Reithrodon clade had strong support, all sister-group relationships involving Abrawayaomys lacked any significant support.
As such, Abrawayaomys constitutes the only representative so far known of one of the main lineages of the sigmodontine radiation, differing from all other Atlantic forest sigmodontine rodents by having a unique combination of morphological character states. Therefore, in formal classifications, it should be regarded as a Sigmodontinae incertae sedis.
- Atlantic forest
With about 86 living genera, cricetids of the subfamily Sigmodontinae are one of the most diversified and taxonomically complex groups of mammals. Predominantly distributed in South America, sigmodontines also reach Central and North America, and one extant genus is endemic to the Galapagos Islands (D'Elía 2003a). Remarkably, new sigmodontine genera are still being erected on the basis of both revisionary museum work and from newly discovered species (e.g., Pardiñas et al. 2009a; Percequillo et al. 2011; Pine et al. 2012; Alvarado-Serrano and D'Elía 2013; see comments in D'Elía and Pardiñas 2007). Similarly, statuses of several sigmodontine taxonomic forms at the species level are unclear (e.g., Alarcón et al. 2011; Bonvicino et al. 2012).
Sigmodontine genera have been arranged into different groups, most of which have been given the formal rank of tribes (e.g., Reig 1980). In the last two decades, phylogenetic analyses using either morphological or molecular data or both were used to set the limits and contents of these groups and determine the timing of their diversification (e.g., Braun 1993; Smith and Patton 1999; Steppan 1995;D'Elía 2003b; Pacheco 2003; Weksler 2003; D'Elía et al. 2003, D'Elia et al. 2006a, b; Martínez et al. 2012; Parada et al. 2013; Salazar-Bravo et al. 2013). Those studies caused a number of major reconsiderations on the limits and contents of these groups. Currently, 12 extant genera are considered as Sigmodontinae incertae sedis (see the most recently published classification in D'Elía et al. (2007) and the modification prompted by the description of a new genus by Alvarado-Serrano and D'Elía (2013)); one of these is Abrawayaomys Cunha and Cruz 1979.
Abrawayaomys is a poorly known sylvan sigmodontine genus that stands out within the sigmodontine radiation due to its spiny pelage and unusual craniodental morphology. It is found in the Atlantic forest of Argentina and Brazil and is known from a handful of trapped specimens and a few osteological remains gathered from owl pellets (Pardiñas et al. 2009b). Two species are recognized: the type species Abrawayaomys ruschii Cunha and Cruz 1979 and the recently described Abrawayaomys chebezi (Pardiñas et al. 2009a,2009b).
Abrawayaomys displays a striking combination of morphological features that was referred by Musser and Carleton (2005, p. 1,088) in the following terms ‘Diagnostic traits seem to combine aspects of Neacomys, Oryzomys, and Akodon, and both Reig (1987) and Smith and Patton (1999) acknowledged the enigmatic affinities of Abrawayaomys as uncertain.’ Recently, Pardiñas et al. (2009b) evaluated the morphology of Abrawayaomys in detail and noted a certain resemblance to the bauplan of the tribe Akodontini but also to the thomasomyine genera Chilomys and Rhagomys. Similarities with Akodontini were regarded as convergences since Abrawayaomys was assigned to Thomasomyini given that independent sets of data placed Chilomys and Rhagomys in Thomasomyini (D'Elía et al. 2006a; Salazar-Bravo and Yates 2007) and because morphology-based phylogenetic analyses placed Abrawayaomys in this tribe (Pacheco 2003; Salazar-Bravo and Yates 2007). The lack of molecular data for Abrawayaomys has prevented an assessment of its position within the available comprehensive sigmodontine trees generated on the basis of mitochondrial and nuclear DNA sequences (e.g., Engel et al. 1998; Smith and Patton 1999; D'Elía 2003b; Weksler 2003; D'Elia et al. 2006a, b).
In recent fieldwork in the states of Rio de Janeiro (Pereira et al. 2008), Minas Gerais (Passamani et al. 2011), and São Paulo (see below) in southeastern Brazil, four specimens referred to as A. ruschii were collected. Based on mitochondrial and nuclear DNA sequences gathered from these specimens, we present the first phylogenetic analyses to test previous hypotheses concerning the placement of Abrawayaomys within the sigmodontine radiation. In addition, we provide some taxonomic judgments based on the resulting phylogeny and comments on the evolution of some morphological traits.
DNA sequences corresponding to the cytochrome (Cyt) b gene and the first exon of the nuclear interphotoreceptor retinoid-binding protein (IRBP) gene were used as evidence. We sequenced four specimens of A. ruschii deposited in the following Brazilian collections: Museu Nacional, Univ. Federal do Rio de Janeiro (MN 67557; Brazil, Rio de Janeiro, Aldeia Sapucai) (Pereira et al. 2008); Museu de Zoologia, Univ. de São Paulo (MZUSP 32319; Brazil, São Paulo, Biritiba-Mirim; BO 27; Brazil, São Paulo, Estação Ecológica de Boracéia); and Coleção de Mamíferos da Univ. Federal de Lavras (CMUFLA 906; Brazil, Minas Gerais, Caeté) (Passamani et al. 2011). Sequences were gathered following the protocol of Pardiñas et al. (2003) and D'Elía et al. (2006b). We found minor differences among Cyt b sequences (see ‘Results’ below), but in the phylogenetic analyses, we used that of specimen MN 67557 because it was the only complete one (i.e., 1,140 bp; the other being 801 bp long). We found no variation in IRBP sequences of the four specimens analyzed, and therefore, Abrawayaomys was represented by a single terminal (MN 67557) in the phylogenetic analyses. New sequences were submitted to GenBank [GenBank: JX949182 to JX949189].
List of taxa and the DNA sequences of which were included in the phylogenetic analyses
Phyllotini n. gen.
Alignment was done with Clustal X (Thompson et al. 1997) using default parameters for all alignment parameters. Uncorrected genetic distances (p distances) with pairwise deletions were computed using MEGA 5 (Tamura et al. 2011). Each matrix was subjected to maximum-likelihood (ML) (Felsenstein 1981) and Bayesian analyses (BA) (Rannala and Yang 1996). The ML analysis was conducted in Treefinder (Jobb et al. 2004; Jobb 2008). The best fitting models of nucleotide substitution (IRBP: TVM[Optimum, Empirical]:G[Optimum]:5; Cyt b: GTR[Optimum, Empirical]:G[Optimum]:5) (see Jobb 2008) were selected with the Akaike information criterion in Treefinder using the ‘propose model’ routine. The best tree was searched under the model of nucleotide substitutions previously selected using search algorithm 2 implemented in Treefinder version March 2011; nodal support was estimated with 1,000 bootstrap pseudoreplicates (BS). The BA was conducted using MrBayes 3.1.2 (Ronquist and Huelsenbeck 2003) by means of two independent runs with three (IRBP) or seven (Cyt b) heated and one cold Markov chains each. Considering the model selected by Treefinder and models specified in MrBayes, a model with six categories of a base substitution, a gamma-distributed rate parameter, and a proportion of invariant sites was specified for both matrices; all model parameters were estimated using MrBayes. Runs were allowed to proceed for 20 million (IRBP) and 28 million (Cyt b) generations, and trees were sampled every 1,000 (IRBP) and 2,000 (Cyt b) generations. Log-likelihood values were plotted against the generation time to check that runs converged on a stable log-likelihood value. The first 25% of sampled trees were discarded as burn-in; the remaining trees were used to compute a 50% majority rule consensus tree and obtain posterior probability (PP) estimates for each clade.
Cyt b gene sequences of Abrawayaomys gathered from the three specimens collected in the states of São Paulo and Rio de Janeiro varied by 0.5% ~ 0.7%; while comparisons involving the Cyt b sequence of the specimen from Minas Gerais ranged 2.6% ~ 3.0%. As mentioned above, IRBP sequences of the four specimens analyzed were identical.
Abrawayaomys, as represented by sequences of specimen MN 67557, was highly divergent from all compared sigmodontines for both analyzed genes. For the Cyt b gene, observed pairwise values involving Abrawayaomys ranged 19.0% ~ 25.9% for comparisons with Neotomys and Lundomys. For the IRBP gene, observed pairwise values involving Abrawayaomys ranged 3.42% ~ 6.65% for comparisons with Brucepattersonius and Rheomys.
Phylogenetic analyses recovered general results congruent with those of previous IRBP- and/or Cyt b-based studies (e.g., D'Elia et al. 2006a, b; Percequillo et al. 2011; Martínez et al. 2012; Parada et al. 2013; Salazar-Bravo et al. 2013). For descriptions and discussions of these findings (e.g., a strongly supported Sigmodontinae, a strongly supported Oryzomyalia, the polyphyly of the Reithrodon group, and differences between gene trees), we refer the reader to those studies because herein we focus on the phylogenetic position of Abrawayaomys.
The diversity of sigmodontine forms has long captivated students of New World mammals, but at the same time, it has seriously defied those attempting to classify them according to their evolutionary history. Problems range from species boundaries to relationships among species and genera, and limits and contents of higher taxa (e.g., tribes). These issues have direct implications for the study of the history of the diversification of the group, which in turn arguably constitutes one of the most controversial debates in muroid systematics (Voss 1993; D'Elía 2003b).
Herein, we showed that the phylogenetic position of Abrawayaomys varies from being sister to Akodontini, Thomasomyini, Reithrodontini, or Neotomys, depending on the gene analyzed (IRBP or Cyt b) and the analysis performed (ML or BA). Given that previous studies showed discrepancies between the topologies of different sigmodontine gene trees (e.g., Feijoo et al. 2010; Teta et al. 2011), the fact that different datasets (i.e., IRBP or Cyt b matrices with slightly different taxonomic sampling) provide different relationships for Abrawayaomys is not unexpected. Importantly, with the exception of the BA based on Cyt b sequences (sister to Reithrodontini), no sister relationship involving Abrawayaomys was recovered that had good support. In light of the analytical results, Abrawayaomys cannot be placed with certainty in any more inclusive clade than that of Oryzomyalia (sensu Steppan et al. 2004).
Morphological comparisons among Abrawayaomys and other members of the Sigmodontinae
Relation of tail length (LT) to head-body length (HB)
LT < = > HB
LT ≤ HB
LT > > HB
LT < = > HB
LT > HB
LT ≤ HB
LT < < HB
Long, rostral tube developed
Hourglass-shaped or slightly convergent, with rounded margins
Convergent, with beaded margins
Hourglass-shapede, with beaded margins
Hourglass-shaped, with rounded margins
Hourglass-shaped, with rounded margins
Hourglass-shaped, with rounded margins
Symmetrically constricted, with parallel margins
Does not overlap squamosal
Intermediate to alternate, crested
Intermediate, crested to terraced
Mesoloph on M1
M3 reduction to M2
Moderately to reduced
Orthodont to proodont
Reaching anterior face M1
Reaching anterior face M1
Reaching anterior face M1
Reaching anterior face M1
Reaching protocone M1
Reaching protocone M1
Number of ribs
The prevailing biogeographic view is that the Andes played a major role in sigmodontine diversification, in which the main sigmodontine lineages originated there and later colonized lowlands of South America (Reig 1984,1986; see also Salazar-Bravo et al. 2013). However, Abrawayaomys, an Atlantic forest endemic, is the sole living representative of one of the main sigmodontine lineages (i.e., those classified at the tribal rank in formal classifications or those genera that do not belong to any recognized tribe). A similar scenario was found for two other Atlantic forest endemics, the genera Delomys and Juliomys (Figures 1 and 2) (Voss 1993; D'Elía et al. 2006a; see also the classification in D'Elía et al. 2007). The other main sigmodontine lineages are distributed outside the Atlantic forest (e.g., Abrotrichini and Sigmodontini) or, even when present in this biome, are not endemic to it (e.g., Akodontini and Oryzomyini). As mentioned above, the Atlantic forest-endemic Phaenomys and mostly Atlantic forest-resident Wilfredomys have not been included in any molecular-based phylogenetic analysis. Until their phylogenetic position is assessed, it is unclear whether they in fact represent additional main sigmodontine lineages almost endemic to the Atlantic forest or simply constitute additional genera belonging to other already identified main lineages of the Sigmodontinae either already known from the Atlantic forest or not. Whatever this result is, the finding that at least three unrelated main sigmodontine lineages, those currently represented by Abrawayaomys, Delomys, and Juliomys, are endemic to the southern Atlantic forest supports early claims (Smith and Patton 1999; D'Elía 2003b; see also Salazar-Bravo et al. 2013) highlighting the role of the Atlantic forest in harboring sigmodontine phylogenetic diversity. Future studies should be designed to test if these lineages originated in the Atlantic forest or simply invaded it after originating elsewhere.
Spines of varying hardness and architectures are present in several rodents (Chernova and Kuznetsov 2001) and are conspicuous in some Neotropical groups, such as porcupines (Erethizontidae) and spiny rats (Echimyidae). The vast majority of sigmodontine rodents have soft fur, but a few genera and species have dorsal spines. These spines are present in both species of Abrawayaomys, both species of Scolomys, all eight species of Neacomys, but only in one of the two species of Rhagomys. Rhagomys longilingua from the Andes has spiny fur, but Rhagomys rufescens from the Atlantic forest has soft fur (Luna and Patterson 2003). Considering the phylogeny portrayed here, we concluded that these spines are the result of evolutionary convergence, and this trait evolved at least four times in sigmodontines (Figure 1). None of these four genera are sister groups, and each one of them shares a more recent common ancestor with soft-furred genera or species (in the case of Rhagomys). The functional significance of spines remains unknown. Unlike porcupine quills, spines of muroid or echimyid rodents are insufficiently rigid to provide much protection against predators, including snakes, birds, and mammals, which are known to prey heavily on many spiny species (Hoey et al. 2004). Patterson and Velazco (2008) suggested a thermoregulatory interpretation based on the geographic distribution of echimyid rodents: the spiniest members occur in tropical lowland forests, while many of the softest-haired members of the family range into high elevations or latitudes, but they also noted several exceptions. The same pattern does not occur in sigmodontine rodents, since soft-furred taxa occur at all latitudes and elevations throughout the Neotropics. Regarding spiny taxa, both Neacomys and Scolomys are lowland forest genera found at lower latitudes (Patton et al. 2000); Abrawayaomys also occurs in lowland forests, but at higher latitudes in the Atlantic forest (Pardiñas et al. 2009b); and the spiny R. longilingua is found in Andean cloud forests at 1,900 ~ 2,100 m in elevation (Luna and Patterson 2003), while the soft-furred R. rufescens occurs mostly in montane Atlantic forest at 500 ~ 1,000 m in elevation (Steiner-Souza et al. 2008). Therefore, we still lack robust hypotheses for the ecological role, if any, of spiny fur in sigmodontine rodents, but the character distribution mapped on a phylogenetic tree presented here is the first step toward understanding its evolutionary importance.
Phylogenetic analyses show that Abrawayaomys constitutes the single representative so far known of one of the main lineages of the radiation of Sigmodontinae. In addition, it differs from all other Atlantic forest sigmodontine rodents by having a unique combination of morphological character states. Therefore, in formal classifications, it should be regarded as a Sigmodontinae incertae sedis.
Finally, the observed variation of the four Cyt b sequences analyzed and their geographic pattern, where the one gathered from the northernmost-collected specimen (in the state of Minas Gerais) was the most divergent, are enticing to further explore variation of a larger sample of A. ruschii sequences. Such a study would clarify into which of the already known phylogeographic patterns of Atlantic forest mammals (e.g., Colombi et al. 2010; Ventura et al. 2012; Valdez and D'Elía 2013; see reviews in Martins 2011; Costa and Leite 2012) would A. ruschii fit, or if this species presents a so far undescribed pattern. Similarly, such a study would help assess the alpha diversity of Abrawayaomys (Pardiñas et al. 2009b). Now, that A. ruschii is becoming more frequent in specimen collections, such a study seems feasible.
We thank André Almeida Cunha, Arlei Marcili, Caroline Cotrim Aires, Laerte Bento Viola, Marcelo Passamani, Patricia B. Bertola, Renata Pardini, and Sandra Favorito for support with fieldwork and collecting specimens, and Juliana F. Justino for producing some of the DNA sequences. Two anonymous reviewers provided valuable comments on an earlier version of this contribution. This work was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES-BEX 3795/08-0) (to LG), Fundação de Amparo a Pesquisa do Estado de São Paulo BP.PD 2009/54300-0 (to KV), JP 05/07553-8 (to MJJS), Fundação de Amparo à Pesquisa do Espírito Santo (to YLRL), Fundação de Amparo do Estado do Rio de Janeiro (FAPERJ-E-26/111.525/2010) (to LG), PICT (Agencia) 2008–547 (to UFJP), Fondo Nacional de Desarrollo Científico y Tecnólogico 1110737 (to GD), and MECESUP AUS1203 (to GD).
- Alarcón O, D'Elía G, Lessa E, Pardiñas UFJ: Phylogeographic structure of the fossorial long-clawed mouse Chelemys macronyx (Cricetidae: Sigmodontinae). Zool Stud 2011, 50: 682–688.Google Scholar
- Alvarado-Serrano D, D'Elía G: A new genus for the Andean mice Akodon latebricola and A. bogotensis (Rodentia: Sigmodontinae). J Mamm 2013, 94: 995–1015. 10.1644/12-MAMM-A-276.1View ArticleGoogle Scholar
- Andrades-Miranda J, Zanchin NIT, Oliveira LFB, Langguth A, Mattevi MS: Cytogenetic studies in nine taxa of the genus Oryzomys (Rodentia, Sigmodontinae) from Brazil. Mammalia 2000, 65: 461–472.Google Scholar
- Bonvicino CR, Lindbergh SM, Barros M, Bezerra AMR: The eastern boundary of the Brazilian Cerrado: a hotspot region. Zool Stud 2012, 51: 1207–1218.Google Scholar
- Braun JK: Systematic relationships of the tribe Phyllotini (Muridae: Sigmodontinae) of South America. Oklahoma Museum of Natural History, Norman, OK; 1993.Google Scholar
- Carleton MD: A survey of gross stomach morphology in New World cricetine (Rodentia, Muroidea) with comments on functional interpretations. Misc Publ Mus Zool Univ Michigan 1973, 146: 1–43.Google Scholar
- Chernova OF, Kuznetsov GV: Structural features of spines in some rodents (Rodentia: Myomorpha, Hystricomorpha). Biol Bull 2001, 28: 371–382. 10.1023/A:1016623123957View ArticleGoogle Scholar
- Colombi VH, Lopes SR, Fagundes V: Testing the Rio Doce as a riverine barrier in shaping the Atlantic rainforest population divergence in the rodent Akodon cursor . Genet Mol Biol 2010, 33: 785–789. 10.1590/S1415-47572010000400029PubMed CentralView ArticlePubMedGoogle Scholar
- Costa LP, Leite YL: Historical fragmentation shaping vertebrate diversification in the Atlantic forest biodiversity hotspot. In Bones, clones, and biomes: the history and geography of recent Neotropical mammals. Edited by: Patterson BD, Costa LP. Univ. of Chicago Press, Chicago; 2012:283–306.View ArticleGoogle Scholar
- D'Elía G: Rats, mice, and relatives IV: Sigmodontinae. 16 of Grzimek's animal life encyclopedia, 1st ed. In Mammals. Volume vol 16. Edited by: Kleiman DG, Geist V, Hutchins M, McDade MC. Thomson-Gale, Farmington Hills, MI; 2003a:263–279.Google Scholar
- D'Elía G: Phylogenetics of sigmodontinae (Rodentia, Muroidea, Cricetidae), with special reference to the akodont group, and with additional comments on historical biogeography. Cladistics 2003b, 19: 307–323.View ArticleGoogle Scholar
- D'Elía G, Pardiñas UFJ: Putting names to the phylogenetic diversity of Neotropical sigmodontine rodents: new genera for known species. Mammalia 2007, 71: 143–145.View ArticleGoogle Scholar
- D'Elía G, González EM, Pardiñas UFJ: Phylogenetic analysis of sigmodontine rodents (Muroidea), with special reference to the akodont genus Deltamys . Mamm Biol 2003, 68: 351–364.Google Scholar
- D'Elia G, Luna L, Gonzalez EM, Patterson BD: On the Sigmodontinae radiation (Rodentia, Cricetidae): an appraisal of the phylogenetic position of Rhagomys . Mol Phylogenet Evol 2006a, 38: 558–564. 10.1016/j.ympev.2005.08.011View ArticleGoogle Scholar
- D'Elia G, Ojeda AA, Mondaca F, Gallardo MH: New data of the tong-clawed mouse Pearsonomys annectens (Cricetidae, Sigmodontinae) and additional comments on the distinctiveness of Pearsonomys . Mamm Biol 2006b, 71: 39–51.Google Scholar
- D'Elía G, Pardiñas UFJ, Teta P, Patton JL: Definition and diagnosis of a new tribe of sigmodontine rodents (Cricetidae: Sigmodontinae), and a revised classification of the subfamily. Gayana 2007, 71: 187–194.Google Scholar
- Engel SR, Hogan KM, Taylor JF, Davis SK: Molecular systematics and paleobiogeography of the South-American sigmodontine rodents. Mol Biol Evol 1998, 15: 35–49. 10.1093/oxfordjournals.molbev.a025845View ArticlePubMedGoogle Scholar
- Feijoo M, D'Elía G, Pardiñas UFJ, Lessa EP: Systematics of the southern Patagonian-Fueguian endemic Abrothrix lanosus (Rodentia: Sigmodontinae): phylogenetic position, karyotypic and morphological data. Mamm Biol 2010, 75: 122–137.Google Scholar
- Felsenstein J: Evolutionary trees from DNA sequences: a maximum likelihood approach. J Mol Evol 1981, 17: 368–376. 10.1007/BF01734359View ArticlePubMedGoogle Scholar
- Finotti R, Cunha A, Cerqueira R: Alimentação macroscópica do trato digestivo de Abrawayaomys ruschii. Abstracts of the II Congresso Brasileiro de Mastozoologia, Belo Horizonte, Brazil; 2003.Google Scholar
- Geise L, Weksler M, Bonvicino CR: Presence or absence of gall bladder in some Akodontini rodents (Muridae, Sigmodontinae). Mamm Biol 2004, 69: 210–214.Google Scholar
- Hershkovitz P: Evolution of Neotropical cricetine rodents (Muridae) with special reference to the phyllotine group. Fieldiana Zool 1962, 46: 1–524.Google Scholar
- Hoey KA, Wise RR, Adler GH: Ultrastructure of echimyid and murid rodent spines. J Zool 2004, 263: 307–315. 10.1017/S0952836904005370View ArticleGoogle Scholar
- Jobb G: Treefinder version of April 2008. 2008.Google Scholar
- Jobb G, Haeseler A, Strimmer K: TREEFINDER: a powerful graphical analysis environment for molecular phylogenetics. BMC Evol Biol 2004, 4: 18. 10.1186/1471-2148-4-18PubMed CentralView ArticlePubMedGoogle Scholar
- Luna L, Patterson BD: A remarkable new mouse (Muridae: Sigmodontinae) from southeastern Peru: with comments on the affinities of Rhagomys rufescens . Fieldiana Zool 2003, 101: 1–24.Google Scholar
- Martínez JJ, Ferro LI, Mollerach MI, Barquez RM: The phylogenetic relationships of the Andean swamp rat genus Neotomys (Rodentia, Cricetidae, Sigmodontinae) based on mitochondrial and nuclear markers. Acta Theriol 2012, 57: 277–287. 10.1007/s13364-011-0070-9View ArticleGoogle Scholar
- Martins FD: Historical biogeography of the Brazilian Atlantic forest and the Carnaval-Moritz model of Pleistocene refugia: what do phylogeographical studies tell us? Biol J Linn Soc 2011, 104: 499–509. 10.1111/j.1095-8312.2011.01745.xView ArticleGoogle Scholar
- Musser GG, Carleton MD: Superfamily Muroidea. In Mammal species of the world: a taxonomic and geographic reference. 3rd edition. Edited by: Wilson DE, Reeder DM. Johns Hopkins Univ. Press, Baltimore, MD; 2005:894–1531.Google Scholar
- Myers P, Carleton MD: The species of Oryzomys ( Oligoryzomys ) in Paraguay and the identity of Azara's "rat sixième ou rat à tarse noir". Misc Publ Mus Zool Univ Michigan 1981, 161: 1–41.Google Scholar
- Pacheco VR PhD thesis. In Phylogenetic analyses of the Thomasomyini (Muroidea: Sigmodontinae) based on morphological data. City Univ. of New York, New York; 2003.Google Scholar
- Parada A, Pardiñas UFJ, Salazar-Bravo J, D'Elía G, Palma ER: Dating an impressive Neotropical radiation: molecular time estimates for the Sigmodontinae (Rodentia) provide insights into its historical biogeography. Mol Phylogen Evol 2013, 66: 960–968. 10.1016/j.ympev.2012.12.001View ArticleGoogle Scholar
- Pardiñas UFJ, D'Elía G, Cirignoli S: The genus Akodon (Muroidea: Sigmodontinae) in Misiones, Argentina. Mamm Biol 2003, 68: 129–143.Google Scholar
- Pardiñas UFJ, D'Elía G, Teta P: Una introducción a los mayores sigmodontinos vivientes: revisión de Kunsia Hershkovitz, 1966 y descripción de un nuevo género (Rodentia: Cricetidae). Arq Mus Nacl Rio de Janeiro 2009a, 66: 509–594.Google Scholar
- Pardiñas UFJ, Teta P, D'Elía G: Taxonomy and distribution of Abrawayaomys (Rodentia: Cricetidae), an Atlantic forest endemic with the description of a new species. Zootaxa 2009b, 2128: 39–60.Google Scholar
- Passamani M, Cerboncini RAS, Oliveira JE: Distribution extension of Phaenomys ferrugineus (Thomas, 1894), and new data on Abrawayaomys ruschii Cunha and Cruz, 1979 and Rhagomys rufescens (Thomas, 1886), three rare species of rodents (Rodentia: Cricetidae) in Minas Gerais, Brazil. CheckList 2011, 7: 827–831.Google Scholar
- Patterson BD, Velazco PM: Phylogeny of the rodent genus Isothrix (Hystricognathi, Echimyidae) and its diversification in Amazonia and the eastern Andes. J Mamm Evol 2008, 15: 181–201. 10.1007/s10914-007-9070-6View ArticleGoogle Scholar
- Patton JL, da Silva MNF, Malcolm JR: Mammals of the Rio Juruá and the evolutionary and ecological diversification of Amazonia. Bull Am Mus Nat Hist 2000, 244: 1–306. 10.1206/0003-0090(2000)244<0001:MOTRJA>2.0.CO;2View ArticleGoogle Scholar
- Percequillo AR, Weksler M, Costa LP: A new genus and species of rodent from the Brazilian Atlantic forest (Rodentia: Cricetidae: Sigmodontinae: Oryzomyini), with comments on oryzomyine biogeography. Zool J Linn Soc 2011, 161: 357–390. 10.1111/j.1096-3642.2010.00643.xView ArticleGoogle Scholar
- Pereira LG, Geise L, Cunha AA, Cerqueira R: Abrawayaomys ruschii Cunha & Cruz, 1979 (Rodentia, Cricetidae) no estado do Rio de Janeiro, Bra. 2008, 33–40.Google Scholar
- Pine RH, Timm RM, Weksler M: A newly recognized clade of trans-Andean Oryzomyini (Rodentia: Cricetidae), with description of a new genus. J Mamm 2012, 93: 851–868. 10.1644/11-MAMM-A-012.1View ArticleGoogle Scholar
- Rannala B, Yang ZH: Probability distribution of molecular evolutionary trees: a new method of phylogenetic inference. J Mol Evol 1996, 43: 304–311. 10.1007/BF02338839View ArticlePubMedGoogle Scholar
- Reig OA: A new fossil genus of South American cricetid rodents allied to Wiedomys , with an assessment of the Sigmodontinae. J Zool (Lond) 1980, 192: 257–281.View ArticleGoogle Scholar
- Reig OA: Distribuicao geografica e historia evolutiva dos roedores muroideos sulamericanos (Cricetidae: Sigmodontinae). Rev bras Genet 1984, 7: 333–365.Google Scholar
- Reig OA: Diversity patterns and differentiation of high Andean rodents. In High altitude tropical biogeography. Edited by: Vuilleumier F, Monasterio M. Oxford Univ. Press and American Museum of Natural History, New York and Oxford, UK; 1986:404–439.Google Scholar
- Reig OA: An assessment of the systematics and evolution of the Akodontini, with the description of new fossil species of Akodon (Cricetidae, Sigmodontinae). In Studies in Neotropical Mammalogy, Fieldiana, Zool 39th edition. Edited by: Patterson BD, Timm RM. 1987, 347–399.Google Scholar
- Ronquist F, Huelsenbeck JP: MrBayes 3: Bayesian phylogenetic inference under mixed models. Bioinformatics 2003, 19: 1572–1574. 10.1093/bioinformatics/btg180View ArticlePubMedGoogle Scholar
- Salazar-Bravo J, Yates TL: A new species of Thomasomys (Cricetidae: Sigmodontinae) from central Bolivia. In The quintessential naturalist: honoring the life and legacy of Oliver P. Pearson. 134th edition. Edited by: Kelt DA, Lessa EP, Salazar-Bravo J, Patton JL. Univ. of California Publications in Zoology, Berkeley; 2007:747–774.Google Scholar
- Salazar-Bravo J, Pardiñas UFJ, D'Elía G: A phylogenetic appraisal of Sigmodontinae (Rodentia, Cricetidae) with emphasis on phyllotine genera: systematics and biogeography. Zool Scr 2013, 42: 250–261. 10.1111/zsc.12008View ArticleGoogle Scholar
- Smith MF, Patton JL: Phylogenetic relationships and the radiation of sigmodontine rodents in South America: evidence from cytochrome b. J Mamm Evol 1999, 6: 89–128. 10.1023/A:1020668004578View ArticleGoogle Scholar
- Steiner-Souza F, Cordeiro-Estrela P, Percequillo AR, Testoni AF, Althoff SL: New records of Rhagomys rufescens (Rodentia: Sigmodontinae) in the Atlantic forest of Brazil. Zootaxa 2008, 1824: 28–34.Google Scholar
- Steppan SJ: Revision of the tribe Phyllotini (Rodentia: Sigmodontinae), with a phylogenetic hypothesis for the Sigmodontinae. Fieldiana Zool 1995, 80: 1–112.Google Scholar
- Steppan SJ, Adkins RM, Anderson J: Phylogeny and divergence-date estimates of rapid radiations in muroid rodents based on multiple nuclear genes. Syst Biol 2004, 53: 533–553. 10.1080/10635150490468701View ArticlePubMedGoogle Scholar
- Tamura K, Peterson D, Peterson N, Stecher G, Nei M, Kumar S: MEGA5: molecular evolutionary genetics analysis using maximum likelihood, evolutionary distance, and maximum parsimony methods. Mol Biol Evol 2011, 28: 2731–2739. 10.1093/molbev/msr121PubMed CentralView ArticlePubMedGoogle Scholar
- Teta P, D'Elía G, Pardiñas UFJ, Jayat JP, Ortíz PE: Phylogenetic position and morphology of Abrothrix illutea Thomas, 1925, with comments on the incongruence between gene trees of Abrothrix (Rodentia, Cricetidae) and their implications for the delimitation of the genus. Zoosyst Evol 2011, 87: 227–241. 10.1002/zoos.201100005View ArticleGoogle Scholar
- Thompson JD, Gibson TJ, Plewniak F, Jeanmougin F, Higgins HG: The Clustal X windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucl A Res 1997, 24: 4876–4882.View ArticleGoogle Scholar
- Valdez L, D'Elía G: Differentiation in the Atlantic forest: phylogeography of Akodon montensis (Rodentia, Sigmodontinae) and the Carnaval-Moritz model of Pleistocene refugia. J Mamm 2013, 94: 911–922. 10.1644/12-MAMM-A-227.1View ArticleGoogle Scholar
- Ventura K, Sato-Kuwabara Y, Fagundes V, Geise L, Leite YLR, Silva MJJ, Yonenaga-Yassuda Y, Rodrigues MT: Phylogeographic structure and karyotypic diversity of the Brazilian shrew mouse ( Blarinomys breviceps , Sigmodontinae) in the Atlantic forest. Cytogenet Genome Res 2012, 138: 19–30. 10.1159/000341887View ArticlePubMedGoogle Scholar
- Voss RS: A revision of the Brazilian muroid rodent genus Delomys with remarks on “thomasomyine” characters. Am Mus Novit 1993, 3073: 1–44.Google Scholar
- Voss RS, Gomez-Laverde M, Pacheco V: A new genus for Aepeomys fuscatus Allen, 1912 and Oryzomys intectus Thomas, 1921: enigmatic murid rodents from Andean cloud forests. Am Mus Novit 2002, 3373: 42.View ArticleGoogle Scholar
- Weksler M: Phylogeny of Neotropical oryzomyine rodents (Muridae: Sigmodontinae) based on the nuclear IRBP exon. Mol Phylogenet Evol 2003, 29: 331–349. 10.1016/S1055-7903(03)00132-5View ArticlePubMedGoogle Scholar
- Yonenaga-Yassuda Y, Prado RC, Mello DA: Supernumerary chromosomes in Holochilus brasiliensis and comparative cytogenetic analysis with Nectomys squamipes (Cricetidae, Rodentia). Bras J Genet 1987, 2: 209–220.Google Scholar
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