The igneous crust of the oceans and the continents represents the major part of Earth's lithosphere and has recently been recognized as a substantial, yet underexplored, microbial habitat. While prokaryotes have been the focus of most investigations, microeukaryotes have been surprisingly neglected. However, recent work acknowledges eukaryotes, and in particular fungi, as common inhabitants of the deep biosphere, including the deep igneous provinces. The fossil record of the subseafloor igneous crust, and to some extent the continental bedrock, establishes fungi or fungus-like organisms as inhabitants of deep rock since at least the Paleoproterozoic, which challenges the present notion of early fungal evolution. Additionally, deep fungi have been shown to play an important ecological role engaging in symbiosis-like relationships with prokaryotes, decomposing organic matter, and being responsible for mineral weathering and formation, thus mediating mobilization of biogeochemically important elements. In this review, we aim at covering the abundance and diversity of fungi in the various igneous rock provinces on Earth as well as describing the ecological impact of deep fungi. We further discuss what consequences recent findings might have for the understanding of the fungal distribution in extensive anoxic environments and for early fungal evolution.

海洋和大洲的火成硬壳代表了地球岩石圈的主要部分，最近被认为是一个重要的但尚未开发的微生物栖息地。尽管原核生物一直是大多数研究的重点，但微真核生物却被意外地忽略了。然而，最近的工作承认真核生物，尤其是真菌，是深生物圈包括火成岩深省的常见居民。海底火成岩壳的化石记录，在一定程度上为大陆基岩，至少从古元古代开始就将真菌或类真菌生物建立为深层岩石的居民，这挑战了目前早期真菌进化的观念。另外，已证明深部真菌在与原核生物发生共生样关系，分解有机物并负责矿物风化和形成方面起着重要的生态作用，从而调节了生物地球化学重要元素的动员。在这篇综述中，我们旨在涵盖地球上各个火成岩省的真菌的丰富性和多样性，并描述深部真菌的生态影响。我们将进一步讨论最近的发现可能对理解广泛缺氧环境中的真菌分布以及早期真菌进化产生什么后果。我们旨在涵盖地球上各个火成岩省的真菌的丰富性和多样性，并描述深部真菌的生态影响。我们将进一步讨论最近的发现可能对理解广泛缺氧环境中的真菌分布以及早期真菌进化产生什么后果。我们旨在涵盖地球上各个火成岩省的真菌的丰富性和多样性，并描述深部真菌的生态影响。我们将进一步讨论最近的发现可能对理解广泛缺氧环境中的真菌分布以及早期真菌进化产生什么后果。