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Comparative Study
. 2017 Jul 20;12(7):e0181434.
doi: 10.1371/journal.pone.0181434. eCollection 2017.

Oecomys catherinae (Sigmodontinae, Cricetidae): Evidence for chromosomal speciation?

Stella Miranda Malcher  1 , Julio Cesar Pieczarka  1 , Lena Geise  2 , Rogério Vieira Rossi  3 , Adenilson Leão Pereira  1 , Patricia Caroline Mary O'Brien  4 , Paulo Henrique Asfora  5 , Victor Fonsêca da Silva  3 , Maria Iracilda Sampaio  6 , Malcolm Andrew Ferguson-Smith  4 , Cleusa Yoshiko Nagamachi  1
Affiliations
Comparative Study

Oecomys catherinae (Sigmodontinae, Cricetidae): Evidence for chromosomal speciation?

Stella Miranda Malcher et al. PLoS One. .

Abstract

Among the Oryzomyini (Sigmodontinae), Oecomys is the most speciose, with 17 species. This genus presents high karyotypic diversity (2n = 54 to 2n = 86) and many taxonomic issues at the species level because of the presence of cryptic species and the overlap of morphological characters. For these reasons the real number of species of Oecomys may be underestimated. With the aim of verifying if the taxon Oecomys catherinae is composed of more than one species, we made comparative studies on two populations from two regions of Brazil, one from the Amazon and another from the Atlantic Forest using both classical cytogenetics (G- and C-banding) and comparative genomic mapping with whole chromosome probes of Hylaeamys megacephalus (HME), molecular data (cytochrome b mitochondrial DNA) and morphology. Our results confirm that Oecomys catherinae occurs in the southeast Amazon, and reveal a new karyotype for the species (2n = 62, FNa = 62). The comparative genomic analysis with HME probes identified chromosomal homeologies between both populations and rearrangements that are responsible for the different karyotypes. We compared our results in Sigmodontinae genera with other studies that also used HME probes. These chromosomal differences together with the absence of consistent differentiation between the two populations on morphological and molecular analyses suggest that these populations may represent cryptic species.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1. Distribution map of Oecomys catherinae in Brazil.
Geographic distribution of Oecomys catherinae based on Carleton & Musser [1] and Asfora et al. [4] (shaded area) with collecting localities (circles with a dot) of specimens included in this report. 1: Linhares; 2: Pirapetinga; 3: Cachoeiras de Macacu; 4: Cambuci; 5: Casimiro de Abreu; 6: Guapimirim; 7: Sumidouro; 8: Capão Bonito; 9: Ubatuba; 10: Vila Rica; 11: Marabá; 12: Parauapebas. The star represents the type locality (Joinvile).
Fig 2
Fig 2. Karyotype of O. catherinae from Pará.
Oecomys catherinae (2n = 62; FNa = 62) from the state of Pará: a) G-banding with genomic mapping using whole chromosome probes of Hylaeamys megacephalus (2n = 54). b) C-banding showing the Constitutive Heterochromatin location.
Fig 3
Fig 3. Karyotype of O. catherinae from Rio de Janeiro.
Oecomys catherinae (2n = 60; NFa = 62) from the state of Rio de Janeiro: a) G-banding with genomic mapping using whole chromosome probes of Hylaeamys megacephalus (2n = 54). b) C-banding showing the Constitutive Heterochromatin location.
Fig 4
Fig 4. Synthetic blocks between OCA-PA and OCA-RJ.
a) Syntenic association in OCA-PA and OCA-RJ; b) HME 2 painting in OCA-PA and OCA-RJ; c) HME 6 painting in OCA-PA and OCA-RJ. (DAPI = Blue; FITC = Green; Cy3 = Red).
Fig 5
Fig 5. Bayesian inference tree resulted from the analyses of cytochrome b (Cytb) sequences data (Cytb).
Values of bootstrap for ML / posterior probability for BI are shown close to the nodes with phylogenetic interest. For each terminal branch of Oecomys catherinae the alphanumeric identity and the geographic locality is provided. Bold branches refer to the samples for which karyotypic analysis was performed.
See this image and copyright information in PMC

References

    1. Carleton MD, Musser GG. “Genus Oecomys Thomas, 1906”. In Patton JL, Pardiñas UFJ, D’Élia G editors. Mammals of South America. Vol.2, Rodents Chicago, IL: The University of Chicago Press; 2015; pp. 393–417.
    1. Pardiñas UFJ, Teta P, Salazar-Bravo J, Myers P, Galliari CA. A new species of arboreal rat, genus Oecomys (Rodentia, Cricetidae) from Chaco. J Mammal. 2016. http://dx.doi.org/10.1093/jmammal/gyw070. - DOI
    1. Patton JL, Da Silva MNF, Malcolm JR. Mammals of the Rio Juruá and the evolutionary and ecological diversification of Amazonia. Bulletin of The American Museum of Natural History. 2000; pp. 244–306.
    1. Asfora PH, Palma ART, Astúa D and Geise L. Distribution of Oecomys catherinae Tomas, 1909 (Rodentia: Cricetidae) in northeastern Brazil with karyotypical and morphometrical notes. Biota Neotrop. 2011; 11(2): 415–424. doi: 10.1590/S1676-06032011000200039 - DOI
    1. Peppers LL, Bradley RD. Molecular systematics of the genus Sigmodon. J Mammal 2000; 81 (2): 332–343. http://dx.doi.org/10.1644/1545-1542(2000)081<0332:CSISHE>2.0.CO;2. - DOI

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