Fungivorous millipedes (subterclass Colobognatha) likely represent some of the earliest known mycophagous terrestrial arthropods, yet their fungal associates remain elusive. Here we describe relationships between fungi and the fungivorous millipede, Brachycybe lecontii. Their fungal community is surprisingly diverse, including 176 genera, 39 orders, four phyla, and several undescribed species. Of particular interest are twelve genera conserved across wood substrates and millipede clades that comprise the core fungal community of B. lecontii. Wood decay fungi, long speculated to serve as the primary food source for Brachycybe species, were absent from this core assemblage and proved lethal to millipedes in pathogenicity assays while entomopathogenic Hypocreales were more common in the core but had little effect on millipede health. This study represents the first survey of fungal communities associated with any colobognath millipede, and these results offer a glimpse into the complexity of millipede fungal communities.

食真菌千足虫（Colobognatha 亚纲）可能代表了一些最早已知的食菌陆生节肢动物，但它们的真菌伙伴仍然难以捉摸。在这里，我们描述了真菌和食真菌千足虫Brachycybe lecontii之间的关系。它们的真菌群落极其多样化，包括 176 个属、39 个目、4 个门和几个未描述的物种。特别令人感兴趣的是在木材基质和千足虫分支中保存的十二个属，它们构成了B. lecontii的核心真菌群落。长期以来，人们推测木材腐烂真菌是短草属物种的主要食物来源，但该核心组合中不存在木材腐烂真菌，并且在致病性测定中证明对千足虫具有致命性，而昆虫病原性肉座菌在核心中更为常见，但对千足虫的健康影响不大。这项研究是对与任何疣颌千足虫相关的真菌群落的首次调查，这些结果让人们了解千足虫真菌群落的复杂性。