Episodes of isolation and secondary contact among populations of insects of Nearctic origin during Pleistocene glacial/postglacial climatic cycles had a strong evolutionary influence on the diversity of flies in the genus Rhagoletis in mountainous areas of Mexico. As a series of experiments undertaken to gather support for phylogenetic hypotheses on the origin of three walnut-infesting species in the suavis group, we examined pre- and postzygotic isolation between Rhagoletis completa Cresson, 1929 and R. ramosae Hernández-Ortiz, 1985. Despite morphological, biological, and behavioral differences, these two species were found to be capable of hybridization. Mating experiments in large enclosures revealed asymmetric sexual isolation. There were notable differences in male sexual behavior. While R. ramosae males mated exclusively on host fruit, R. completa males used fruit and alternative mating locations. During fruit-guarding and male-male contests, R. completa and R. ramosae males adopted markedly different wing postures. R. completa females were more reluctant to copulate with heterospecific males than R. ramosae females. During no choice crosses in small enclosures, there was a reduction of egg hatch for the hybrid cross of R. completa males × R. ramosae females. Our results and previous studies on reproductive isolation between other species pairs in the suavis group support a clade in which R. ramosae, R. zoqui Bush, 1966, and R. completa are close relatives all still capable of hybridizing.

在更新世冰川/冰河后气候循环期间，近北区起源的昆虫种群之间的隔离和二次接触事件对墨西哥山区Rhagoletis属的果蝇多样性具有强烈的进化影响。由于一系列的实验着手收集三个核桃的产地为进化假说的支持-中为害品种suavis组，我们研究之间的售前和postzygotic隔离Rhagoletis completa勒松，1929年和R. ramosaeHernández-Ortiz，1985。尽管在形态、生物学和行为方面存在差异，但发现这两个物种能够杂交。在大围场中的交配实验揭示了不对称的性隔离。男性的性行为存在显着差异。虽然R. ramosae男性主机水果完全配合，R. completa男性使用的水果和可选择的配合位置。在水果守卫和雄性比赛中，R. completa和R. ramosae雄性采取了明显不同的翅膀姿势。R. completa雌性比R. ramosae更不愿意与异种雄性交配女性。在小围栏内的无选择杂交期间，R. completa雄性× R. ramosae雌性杂交杂交的卵孵化减少。我们的结果和之前关于suavis组中其他物种对之间生殖隔离的研究支持了一个进化枝，其中R. ramosae、R. zoqui  Bush, 1966 和R. completa是近亲，它们仍然能够杂交。