Department of Entomology, University of California, Riverside, CA 92521, USA.
Proc Biol Sci. 2013 Apr 3;280(1759):20130495. doi: 10.1098/rspb.2013.0495. Print 2013 May 22.
While ant colonies serve as host to a diverse array of myrmecophiles, few parasitoids are able to exploit this vast resource. A notable exception is the wasp family Eucharitidae, which is the only family of insects known to exclusively parasitize ants. Worldwide, approximately 700 Eucharitidae species attack five subfamilies across the ant phylogeny. Our goal is to uncover the pattern of eucharitid diversification, including timing of key evolutionary events, biogeographic patterns and potential cophylogeny with ant hosts. We present the most comprehensive molecular phylogeny of Eucharitidae to date, including 44 of the 53 genera and fossil-calibrated estimates of divergence dates. Eucharitidae arose approximately 50 Ma after their hosts, during the time when the major ant lineages were already established and diversifying. We incorporate host association data to test for congruence between eucharitid and ant phylogenies and find that their evolutionary histories are more similar than expected at random. After a series of initial host shifts, clades within Eucharitidae maintained their host affinity. Even after multiple dispersal events to the New World and extensive speciation within biogeographic regions, eucharitids remain parasitic on the same ant subfamilies as their Old World relatives, suggesting host conservatism despite access to a diverse novel ant fauna.
虽然蚁群为各种各样的共生蚁类提供了栖息地，但很少有寄生蜂能够利用这一巨大资源。一个显著的例外是胡蜂科，它是唯一已知专门寄生蚂蚁的昆虫科。在全球范围内，大约有 700 种胡蜂科物种攻击蚂蚁进化枝中的 5 个亚科。我们的目标是揭示共生蚁类的多样化模式，包括关键进化事件的时间、生物地理模式和与蚂蚁宿主的潜在共进化关系。我们目前提出了最全面的胡蜂科分子系统发育，包括 53 个属中的 44 个以及化石校准的分歧时间估计。胡蜂科大约在 5000 万年前与宿主一起出现，此时主要的蚂蚁谱系已经建立并多样化。我们整合了宿主关联数据来检验共生蚁类和蚂蚁系统发育之间的一致性，发现它们的进化历史比随机预期更相似。在一系列最初的宿主转移之后，胡蜂科内的进化枝保持了对宿主的亲和力。即使在多次向新世界的扩散和生物地理区域内的广泛物种形成之后，胡蜂科仍然寄生在与其旧世界亲缘关系相同的蚂蚁亚科上，这表明尽管有机会接触到多样化的新型蚂蚁动物群，但宿主仍然保守。
