The Amazonian Red Side-Necked Turtle <i>Rhinemys rufipes</i> (Spix, 1824) (Testudines, Chelidae) Has a GSD Sex-Determining Mechanism with an Ancient XY Sex Microchromosome System
Patrik F. Viana,
Eliana Feldberg,
Marcelo B. Cioffi,
Vinicius Tadeu de Carvalho,
Sabrina Menezes,
Richard C. Vogt,
Thomas Liehr,
Tariq Ezaz
Affiliations
Patrik F. Viana
Instituto Nacional de Pesquisas da Amazônia, Coordenação de Biodiversidade, Laboratory of Animal Genetics, Av. André Araújo 2936, Petrópolis, Manaus CEP 69067-375, Brazil
Eliana Feldberg
Instituto Nacional de Pesquisas da Amazônia, Coordenação de Biodiversidade, Laboratory of Animal Genetics, Av. André Araújo 2936, Petrópolis, Manaus CEP 69067-375, Brazil
Marcelo B. Cioffi
Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos SP 13565-090, Brazil
Vinicius Tadeu de Carvalho
Universidade Regional do Cariri, Programa de Pós-Graduação em Diversidade Biológica e Recursos Naturais, Campus do Pimenta, Rua Cel. Antônio Luiz, 1161, Crato CEP 63105-100, Brazil
Sabrina Menezes
Instituto Nacional de Pesquisas da Amazônia, Coordenação de Biodiversidade, Centro de Estudos de Quelônios da Amazônia, Av. André Araújo 2936, Petrópolis, Manaus CEP 69067-375, Brazil
Richard C. Vogt
Instituto Nacional de Pesquisas da Amazônia, Coordenação de Biodiversidade, Centro de Estudos de Quelônios da Amazônia, Av. André Araújo 2936, Petrópolis, Manaus CEP 69067-375, Brazil
Thomas Liehr
Institute of Human Genetics, University Hospital Jena, 07747 Jena, Germany
Tariq Ezaz
Institute for Applied Ecology, Faculty of Science and Technology, University of Canberra, Canberra, ACT 12 2616, Australia
The Amazonian red side-necked turtle Rhynemis rufipes is an endemic Amazonian Chelidae species that occurs in small streams throughout Colombia and Brazil river basins. Little is known about various biological aspects of this species, including its sex determination strategies. Among chelids, the greatest karyotype diversity is found in the Neotropical species, with several 2n configurations, including cases of triploidy. Here, we investigate the karyotype of Rhinemys rufipes by applying combined conventional and molecular cytogenetic procedures. This allowed us to discover a genetic sex-determining mechanism that shares an ancestral micro XY sex chromosome system. This ancient micro XY system recruited distinct repeat motifs before it diverged from several South America and Australasian species. We propose that such a system dates back to the earliest lineages of the chelid species before the split of South America and Australasian lineages.
