Speciation and Dispersal of Fungal Symbiots of Insects (Harpellales) in Eastern North America and Europe

毛菌属是毛菌纲三目之一，是一种寄生在昆虫内脏中的真菌，尤其是石蝇（翼翅目）、蜉蝣目（蜉蝣目）和低等蝇（双翅目：线虫目）。通常情况下，真菌是在昆虫幼虫之间传播的，这就提出了真菌是如何在遥远的地理距离上传播的问题。有证据表明，它们可能有一个寄生生命阶段，在这个阶段，在宿主昆虫的卵巢中形成囊肿，然后将真菌分散并沉积在新的栖息地。这些真菌与寄主昆虫之间的联系的细节鲜为人知，真菌之间的关系以及它们的起源和多样化的解释也鲜为人知。由于寄主昆虫包括许多具有生态和医学重要性的物种（例如，蜉蝣和石蝇、蚊子、黑蝇、蠓），因此昆虫学家对能够导致寄主昆虫绝育的寄生现象的了解非常感兴趣。现场和实验室研究将有助于揭示这些真菌与其宿主之间的相互作用，包括真菌的分子系统发育，这有助于解释它们的多样化和起源。这将使我们更好地了解一组非常神秘的真菌，并使对共生、寄生、历史生物地理学和可能的共同物种形成感兴趣的生物学家能够接触到它的物种。

Abstract Harpellales, one of three orders of the class Trichomycetes, are fungi that live as symbionts in the guts of insects, particularly stoneflies (Plecoptera), mayflies (Ephemeroptera), and lower flies (Diptera: Nematocera). Typically, the fungus is transmitted from larval insect to larval insect, raising questions about how the fungi are dispersed over great geographic distances. Evidence exists that they may have a parasitic life stage in which cysts are formed in the ovaries of host insects that then disperse and deposit fungi in new habitats. Details of the association of these fungi with host insects are poorly known as are relationships among the fungi and explanations for their origins and diversification. Because host insects include many species of ecological and medical importance (e.g., mayflies and stoneflies, mosquitoes, black flies, biting midges), an understanding of parasitism that can result in sterilization of the host insect has great interest to entomologists. Field and laboratory studies will help unravel the interactions between these fungi and their hosts, including a molecular informed phylogeny for the fungi that can help explain their diversification and origins. This will permit a better understanding of a very enigmatic group of fungi, and make its species accessible to biologists interested in symbiosis, parasitism, historical biogeography, and possibly co-speciation.