This is an Accepted Article that has been peer-reviewed and approved for publication in the Insect Science but has yet to undergo copy-editing and proof correction. Please cite this article as doi: 10.1111/1744-7917.12489. This article is protected by copyright. All rights reserved. For: Insect Science Title for subject: Anastrepha boliqua × A. fraterculus habridization Title for authors: J. Rull et al. Correspond with: Juan Rull, PROIMI Biotecnología-CONICET, LIEMEN-División Control Biológico de Plagas, Av. Belgrano y Pje. Caseros, T4001MVB San Miguel de Tucumán, Tucumán, Argentina. email: pomonella@gmail.com Original article Experimental hybridization and reproductive isolation between two sympatric species of tephritid fruit flies in the Anastrepha fraterculus species group Juan Rull 1 , Eduardo Tadeo 2 , Rodrigo Lasa 2 , Christian L. Rodríguez 2 , Alma Altuzar- Molina 2 , and Martín Aluja 2 1 PROIMI Biotecnología-CONICET, LIEMEN-División Control Biológico de Plagas, Av. Belgrano y Pje. Caseros, T4001MVB San Miguel de Tucumán, Tucumán, Argentina, 2 Red de Manejo Biorracional de Plagas y Vectores, Instituto de Ecología, A.C., Xalapa, Veracruz 91070, México. Abstract Among tephritid fruit flies, hybridzation has been found to produce local adaptation and speciation, and in the case of pest species, induce behavioral and ecological alterations that can adversely impact efficient pest management. The fraterculus species group within Anastrepha (Diptera: Tephritidae), is a rapidly radiating aggregate, which includes cryptic species complexes, numerous sister species, and several pest species. Molecular studies have highlighted the possibility of introgression between A. fraterculus and A. obliqua. Reproductive isolation has been studied among morphotypes of the A. fraterculus species