Sato Yukie, Breeuwer Johannes A J, Egas Martijn, Sabelis Maurice W
Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240, 1090 GE, Amsterdam, The Netherlands,
Exp Appl Acarol. 2015 Mar;65(3):277-91. doi: 10.1007/s10493-015-9878-3. Epub 2015 Jan 30.
Closely related species with overlapping distributions often show premating reproductive barriers to avoid hybridization. Stigmaeopsis miscanthi (Saito) is a social spider mite infesting Chinese silver grass, and the species consists of two parapatric groups with frequent contacts within the contact zone. They differ in male-male aggressiveness, male morphology, female diapause traits, and life history parameters. There is incomplete but strong post-mating reproductive isolation between the two groups, and their DNA sequences are slightly different, suggesting that they diverged recently. In this study, we investigated premating reproductive barriers. We found that females from different groups frequently shared nest webs, indicating no barriers in the phase of nest establishment. However, inside nests, males from either group showed less courtship behaviour to females of the other group and they copulated less frequently with them when compared to females of the same group. However, the premating reproductive barrier was incomplete and asymmetric. Females of one group frequently resisted courtship by males from the other group, but females of the other group did not. We conclude that some gene flow may occur in the contact zone between the two groups.
分布重叠的近缘物种通常会表现出交配前的生殖隔离以避免杂交。芒草裂爪螨（Stigmaeopsis miscanthi (Saito)）是一种寄生于芒草的群居性叶螨，该物种由两个邻域分布的类群组成，在接触区域内频繁接触。它们在雄螨攻击性、雄螨形态、雌螨滞育特性和生活史参数方面存在差异。两组之间存在不完全但强烈的交配后生殖隔离，并且它们的DNA序列略有不同，这表明它们是最近才分化的。在本研究中，我们调查了交配前的生殖隔离。我们发现来自不同组的雌螨经常共享巢穴网，这表明在筑巢阶段没有隔离。然而，在巢穴内部，与同组雌螨相比，任一雄螨对另一组雌螨的求偶行为较少，与它们交配的频率也较低。然而，交配前的生殖隔离是不完全且不对称的。一组雌螨经常拒绝另一组雄螨的求偶，但另一组雌螨则不会。我们得出结论，两组之间的接触区域可能会发生一些基因流动。
