Looking for the undiscovered asexual taxa: case studies from lesser studied life modes and habitats

Fungi are vital functional members of the biosphere, playing a crucial role in sustaining ecosystems by maintaining the nutrient balance. Many studies have verified the abundance of fungi across all-natural ecosystems and habitats, such as in forests, fresh-water (including both lentic or lotic), marine environments and deserts. With the focus previously on temperate regions and to a lesser extent biodiversity hotspots, the fungi in other areas remain overlooked. Therefore, it is imperative for mycologists to focus on taxa from these less-studied habitats, those dwelling on a vast number of hosts, and fungi that co-exist with other life forms. Molecular tools have been vital for species identification, in phylogeny, and linking sexual and asexual morphs. Identification of taxa based on the phylogenetic species concept, which relies on multiple loci and concordance of more than one gene genealogy, reduces subjectivity when determining the limits of a phylogenetic species. Large numbers of fungi inhabit biodiversity hotspots; however, they are underexplored owing to the vast diversity present and lack of studies. As examples of illustrating the undiscovered asexual fungi, this paper reports one new genus (Uniappendiculata Tibpromma), six new species (Caprettia lichexanthotricha Aptroot & M.F. Souza, Hermatomyces maharashtraense Rajeshkumar et al., Lichenoconium hawksworthii Flakus et al., Phaeobotryon spiraeae L.X. Zhang & X.L. Fan, Rachicladosporium aridum L. Selbmann & C. Coleine and Uniappendiculata kunmingensis Tibpromma) and one new host and country record (Apiculospora spartii Wijayaw. et al.). The paper discusses the biodiversity rich areas of South-Western China, South America and India, lessstudied habitats (rock inhabiting fungi, lichens with conidiomata and lichenicolous fungi), and geographically widespread, but lesser studied hosts to show substantial studies are needed to reveal the extent of fungal diversity. The impact of discovering cryptic species on cataloguing fungal species numbers is also discussed. Each section exemplifies the status of the current research in that genus and future work that is needed.