Systematics of the genus Oecomys (Sigmodontinae: Oryzomyini): molecular phylogenetic, cytogenetic and morphological approaches reveal cryptic species

Author(s)

Suarez-Villota, Elkin Y. ^{[1, 2]} ; Carmignotto, Ana Paula ^[3] ; Brandao, Marcus Vinicius ^[3] ; Percequillo, Alexandre Reis ^[4] ; Silva, Maria Jose de J. ^[1]

Affiliation

^[1] Inst Butantan, Lab Ecol & Evolucao, Ave Vital Brazil 1500, BR-05503900 Sao Paulo - Brazil

^[2] Univ Austral Chile, Inst Ciencias Marinas & Limnol, Edificio Emilio Pugin, Campus Isla Teja, Valdivia 5110236 - Chile

^[3] Univ Fed Sao Carlos, Dept Biol, Lab Diversidade Anim, Campus Sorocaba, Rodovia Joao Leme Santos, Km 110, BR-18052780 Sao Paulo - Brazil

^[4] Univ Sao Paulo, Escola Super Agr Luiz de Queiroz, Dept Ciencias Biol, Ave Padua Dias 11, BR-13418900 Piracicaba, SP - Brazil

• Document type: Journal article
• Source: ZOOLOGICAL JOURNAL OF THE LINNEAN SOCIETY; v. 184, n. 1, p. 182-210, SEP 2018.
• Web of Science Citations: 4

Abstract

Oecomys is a genus of Neotropical arboreal rodents composed of 17 species with diploid number ranging from 2n = 54 to 86. Despite this high taxonomic and karyotypic diversity, the species-level systematics remains uncertain. We investigated the phylogenetic relationships and species delimitation of Oecomys using multiple approaches based on cytogenetic, molecular (mtDNA and nuDNA sequences) and morphological data sets. Sampling included 73 individuals from 25 localities in Amazonia, Cerrado, Pantanal and the Atlantic Forest, as well as 128 DNA sequences from GenBank. Molecular species boundaries associated with karyotype, morphological characters and geographic distribution led us to recognize 15 distinct lineages in Oecomys. These include five major well-supported clades composed of O. bicolor, O. catherinae, O. cleberi, O. mamorae, O. paricola and O. roberti, which were hypothesized as species complexes with at least eight putative new taxa. Three new karyotypes are also reported for the genus: 2n = 54 (FN = 54), 2n = 62 (FN = 62) and 2n = 70 (FN = 74). Sympatry of up to four species with different diploid numbers recovered in distinct clades illustrates the complex evolutionary history in Oecomys. These data highlight the importance of combining cytogenetic, morphological and geographic information along with molecular coalescent analyses in developing species delimitation scenarios. (AU)

• FAPESP's process: 10/03969-4 - Small mammals (Didelphimorphia, Rodentia) from the state of Mato Grosso, Brazil
• Grantee: Marcus Vinicius Brandão de Oliveira
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 05/04557-3 - Cytogenetic and molecular studies on neotropical small rodents from Brazil
• Grantee: Maria José de Jesus Silva
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 11/20022-3 - Systematics of the small non-volant mammals from the open formations of South America: the case of the genus Cryptonanus (Didelphimorphia: Didelphidae)
• Grantee: Ana Paula Carmignotto
• Support Opportunities: Regular Research Grants