title: Sex chromosomes in mitotic and polytene tissues of Anastrepha fraterculus (Diptera, Tephritidae) from Argentina: a review.
abstract: Cytogenetics, which is considered a fundamental tool to understand basic genetic and genomic issues of species, has greatly contributed to the description of polymorphisms both at inter- and intra-specific level. In fact, cytogenetics was one of the first approaches used to propose Anastrepha fraterculus (Diptera: Tephritidae) as a complex of cryptic species. Different morphological variants of sex chromosomes have been reported among Argentinean populations of Anastrepha fraterculus. However, since this high structural variability in sex chromosomes does not pose a reproductive barrier, their role in speciation is yet to be unveiled. This review provides an update on general aspects of cytogenetics in Argentinean Anastrepha fraterculus populations, focused on the prevalence of X-Y arrangements.
authors.affiliation: Laboratorio de Genética de Insectos de Importancia Económica, Instituto de Genética 'Ewald A. Favret', CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.
authors.forename: María Cecilia
authors.initials: MC
authors.lastname: Giardini
authors.affiliation: Laboratorio de Genética de Insectos de Importancia Económica, Instituto de Genética 'Ewald A. Favret', CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.
authors.forename: Fabián H
authors.initials: FH
authors.lastname: Milla
authors.affiliation: Laboratorio de Genética de Insectos de Importancia Económica, Instituto de Genética 'Ewald A. Favret', CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.
authors.forename: Silvia
authors.initials: S
authors.lastname: Lanzavecchia
authors.affiliation:  Grupo de Investigación en Biología Evolutiva, Departamento de Ecología, Genética y Evolución, IEGEBA-Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Mariela
authors.initials: M
authors.lastname: Nieves
authors.affiliation: Laboratorio de Genética de Insectos de Importancia Económica, Instituto de Genética 'Ewald A. Favret', CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.
authors.forename: Jorge L
authors.initials: JL
authors.lastname: Cladera
keywords: Cytogenetics; South American fruit fly; centromeres; heterochromatin; karyotype variants; ribosomal genes