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

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.

SUBMITTER: Malcher SM

PROVIDER: S-EPMC5519095 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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

Malcher Stella Miranda SM Pieczarka Julio Cesar JC Geise Lena L Rossi Rogério Vieira RV Pereira Adenilson Leão AL O'Brien Patricia Caroline Mary PCM Asfora Paulo Henrique PH Fonsêca da Silva Victor V Sampaio Maria Iracilda MI Ferguson-Smith Malcolm Andrew MA Nagamachi Cleusa Yoshiko CY

PloS one 20170720 7

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 pop ...[more]

PMID: 28727788

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Dataset Information

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

Publications

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

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