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The southwest mountainous region of China has been characterized as one of the worldwide biodiversity hotspots, but mechanisms underlying diversification of organisms in this region are still not clear. We assessed whether fragmented mountainous habitats and Pleistocene climate changes impacted the genetic diversity and diversification patterns of the hoary bamboo rat (Rhizomys pruinosus Blyth), a widely distributed species of rodent in SW China. Genetic diversity analyses were undertaken based on four mitochondrial DNA regions and 12 nuclear microsatellite loci (simple sequence repeats), representing 153 individuals from 24 populations across SW China. Moreover, we investigated correlations between genotype and geographical components, and predicted species distribution models for R. pruinosus under the historical and present climate conditions. Both mitochondrial DNA and simple sequence repeat markers revealed substantial genetic diversity and strong differentiation between populations. Phylogeographical analyses revealed two phylogenetic clades that were consistent with their geographical distributions (eastern and western clades). We inferred that the divergence of R. pruinosus was largely driven by Quaternary climatic oscillations and regionally fragmented mountainous habitats with environmental and geographical heterogeneity. Overall, our study revealed diversification patterns of R. pruinosus—patterns that may be shared by small alpine vertebrates in SW China. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A new monotypic Beltrania-like genus, Subsessila, with its type species S. turbinata, is described, illustrated and compared with similar genera. The new genus is introduced in the family Beltraniaceae based on phylogenetic analysis and morphological characters. Subsessila can be easily distinguished from other Beltrania-like genera by dark setae arising from radially lobed basal cells, mostly lacking macronematous conidiophores. Conidiogenous cells are ampulliform or doliiform and produce turbinate to clavate conidia with rostrate proximal end and rounded distal end. Evidence for establishment of the new genus is provided based on morphological comparison and DNA sequence data analyses. [ABSTRACT FROM AUTHOR]