Asexually reproducing fungi play a significant role in essential processes in managed and wild ecosystems such as nutrients cycling and multitrophic interactions. A large number of such taxa are among the most notorious plant and animal pathogens. In addition, they have a key role in food production, biotechnology and medicine. Taxa without or rare sexual reproduction are distinguished based on their sporulating structures and conidiomata in traditional morphology-based taxonomy. The number, variation and diversity of asexually reproducing taxa are insufficiently known, even though fungi capable of asexual reproduction may provide an untapped, rich biological resource for future exploitation. Currently, ca. 30,000 asexual species belonging to ca. 3800 genera have been reported (including 1388 coelomycetous and 2265 hyphomycetous genera). Recent reports (2017–2020) reiterate that the number of asexually producing fungi is higher than the number of frequently sexually-reproducing fungi. With the advent of molecular tools and the abandonment of the dual nomenclature system for pleomorphic fungi, priority criteria were established and revisited in the latest outline of fungi and fungus-like taxa. However, species numbers and taxonomic boundaries of pleomorphic taxa and their synanamorphs or synasexual morphs have yet to be addressed. The number of species of speciose genera (e.g. Alternaria, Aspergillus, Cercospora, Fusarium, Phoma and Pseudocercospora), cryptic species, species of pleomorphic genera, less studied life modes (such as lichenicolous taxa, taxa from extreme environments) and species from biodiversity-rich areas still need evaluation to achieve more reliable estimates of their diversity. This paper discusses the current knowledge on the matter, with diversity estimates, and potential obstacles in several chapters on (1) speciose genera; (2) pleomorphic genera; (3) cryptic species; (4) well-studied but insufficiently resolved taxa, e.g. leaf inhabiting species, marine fungi, (5) less studied life modes, e.g. lichenicolous, rock-inhabiting fungi, insect-associated and yeast-forming taxa and (6) species from biodiversity-rich areas.

无性繁殖真菌在管理和野生生态系统的基本过程中发挥着重要作用，例如营养循环和多营养相互作用。大量此类类群属于最臭名昭著的动植物病原体。此外，它们在食品生产、生物技术和医药方面也发挥着关键作用。在传统的基于形态的分类学中，没有或很少有性生殖的分类单元是根据其孢子结构和分生孢子形来区分的。尽管能够无性繁殖的真菌可能为未来的开发提供未开发的丰富生物资源，但对无性繁殖类群的数量、变异和多样性仍知之甚少。目前，约。约 30,000 个无性繁殖物种。已报道3800个属（其中腔菌属1388个，丝状菌属2265个）。最近的报告（2017-2020）重申，无性繁殖真菌的数量高于频繁有性繁殖真菌的数量。随着分子工具的出现和多形真菌双重命名系统的放弃，在最新的真菌和类真菌分类群大纲中建立并重新审视了优先标准。然而，多形类群及其同性变体或同性变体的物种数量和分类界限尚未得到解决。物种数量（如链格孢属、曲霉属、尾孢属、镰刀菌属、茎点霉属和假尾孢属）、隐秘种、多形属种、较少研究的生活模式（如地衣类群、来自极端环境的类群）和生物多样性物种富裕地区仍然需要进行评估，以对其多样性进行更可靠的估计。本文讨论了关于该问题的当前知识、多样性估计以及关于（1）物种属的几个章节中的潜在障碍； (2) 多形属； （三）隐秘种； (4) 充分研究但尚未充分解决的类群，例如叶栖物种、海洋真菌，(5) 研究较少的生命模式，例如地衣真菌、岩石栖息真菌、昆虫相关和酵母形成类群，以及 (6) 生物多样性物种- 富裕地区。