title: A novel ZZ/ZW sex chromosome system for the genus Leporinus (Pisces, Anostomidae, Characiformes).
abstract: A wide range of sex chromosome mechanisms, including simple and multiple chromosome systems is characteristic of fishes. The Leporinus genus represent a good model to study sex chromosome mechanisms, because an unambiguous ZZ/ZW sex chromosome system was previously described for seven species, while the remaining studied species of the genus do not show differentiated sex chromosomes. The occurrence of sex chromosomes in Leporinus trifasciatus and Leporinus sp2 from the Araguaia river, Amazon basin, Brazil, was here investigated. ZZ/ZW sex chromosomes were detected for both species. The Z and W chromosome morphology of L. trifasciatus is the same as described for other species of the genus Leporinus. However, the Z and W chromosomes of L. sp2 were quite different in their morphology and banding pattern suggesting that the ZW system of this species have originated independently from the ZW system previously described for other Leporinus.
authors.affiliation: Instituto de Ciências e Letras do Médio Araguaia, Universidade Federal de Mato Grosso, 78698-000 Pontal do Araguaia, MT, Brazil. pvenere@uol.com.br
authors.forename: Paulo Cesar
authors.initials: PC
authors.lastname: Venere
authors.forename: Irani Alves
authors.initials: IA
authors.lastname: Ferreira
authors.forename: Cesar
authors.initials: C
authors.lastname: Martins
authors.forename: Pedro Manoel
authors.initials: PM
authors.lastname: Galetti Júnior
mesh_terms: D000818:Animals; D002871:Chromosome Banding; D005260:Female; D005399:Fishes / Q000145:classification / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D009697:Nucleolus Organizer Region; D012730:Sex Chromosomes; D012733:Sex Differentiation