Kirschsteiniothelia is a saprotrophic genus that occurs in both terrestrial and aquatic habitats. This study introduces a novel species of Kirschsteiniothelia, discovered on the bark of Abies fabri, collected from Yunnan Province, China, and named K. laojunensis. The identification was established through a combination of molecular analyses and morphological characteristics. Kirschsteiniothelia laojunensis is characterized by its large subglobose to globose, black perithecia, clavate, 8-spored asci, fusiform asymmetric ascospores, which are hyaline when immature and become greenish to brown at maturity. This discovery marks the first occurrence of Kirschsteiniothelia on tree bark, with some lichen thallus tissue surrounding the base of the perithecia. Detailed morpho-molecular characterization along with a synopsis table for the genus are provided.

New collections of six Squamarina species from type localities in China were studied. The comparison of morphological characteristics and secondary metabolites with those of the type specimens and phylogenetic analyses suggest that S. callichroa and S. pachyphylla belong to Rhizoplaca, S. semisterilis belongs to Lobothallia and S. chondroderma should be retained in Lecanora temporarily. Only two species, S. kansuensis and S. oleosa, remain in Squamarina. The new combinations Lobothallia semisterilis (H. Magn.) Y. Y. Zhang, Rhizoplaca callichroa (Zahlbr.) Y. Y. Zhang and R. pachyphylla (H. Magn.) Y. Y. Zhang are proposed. Detailed descriptions to aid the identification of these species, distributions and phylogenetic trees, based on multiple collections, are presented. The generic concept of Squamarina is recircumscribed in this study.

Based on an exhaustive sampling of all known Lepidostromatales, a lineage of clavarioid lichen-forming basidiomycetes, we assess (i) the phylogenetic affinities of the six Chinese species currently accommodated in Multiclavula (Cantharellales) based on inferences from the 18S and 28S subunits of the nuclear ribosomal DNA repeat and (ii) the phylogenetic structure among Chinese populations of Lepidostromatales, based on the nuc rDNA ITS1-5.8S-ITS2 (internal transcribed spacer [ITS]) regions. Multiclavula fossicola and M. sinensis belong to the Lepidostromatales and are transferred to Sulzbacheromyces. Chinese reports of M. clara and M. vernalis belong to species of Lepidostromatales, and specimens identified as M. mucida belong to the nonlichenized genus Clavaria. Hence, evidence of Multiclavula occurring in China is lacking. Similarly, L. calocerum is excluded from the Chinese flora. The recently described L. asianum should be regarded as conspecific with S. sinensis. Three new species of Sulzbacheromyces are described: S. bicolor and S. yunnanensis from China and S. miomboensis from the Democratic Republic of Congo. Consequently, Sulzbacheromyces is new to Asia and Africa. A worldwide key to the species of Lepidostromatales is provided.

Dimelaena tibetica is described as a species new to science, characterized by a grayish yellow surface, usually with a covering of white pruina, a crustose thallus, areolate at center, radiate-plicate at margin, adnate apothecia and lacking gyrophoric acid. It differs from other usnic acid-containing Dimelaena species by its plane marginal lobes and adnate apothecia. Based on the study of fresh specimens from the environment of the type locality, Dimelaena altissima is proposed as a new combination. A fresh specimen of Dimelaena oreina (type species of the genus Dimelaena) was collected in the Swiss Alps, in the vicinity of the area where the type material of the species presumably was collected, and a sequence was generated to confirm the phylogenetic position of this genus. All three species share common characters: usnic acid content and a yellowish green upper surface. Descriptions of these species were based on a combination of morphological and phylogenetic analyses. A key and phylogram are provided for these three Dimelaena species which produce usnic acid.

Two new species; Lobothallia crenulata Lun Wang & Y. Y. Zhang, L. lobulata Lun Wang & Y. Y. Zhang and one new variety; L. subdiffracta var. rimosa Lun Wang & Y. Y. Zhang, are reported from China and described, based on morphological, chemical and molecular characters. Phylogenetic analyses showed that these new taxa form monophyletic groups. Lobothallia crenulata and L. lobulata, together with L. hydrocharis, L. radiosa and L. recedens, form a well-supported clade, whereas L. subdiffracta var. rimosa is nested within the samples of L. subdiffracta. Lobothallia crenulata is characterised by its placodioid thallus, thickly pruinose upper surface with a rimose appearance, aspicilioid to lecanorine apothecia with a crenate thalline margin and concave, black and pruinose discs. Lobothallia lobulata is characterised by its placodioid thallus, pruinose upper surface with lobules, aspicilioid when immature, lecanorine to zeorine apothecia at maturity and concave to plane, dark brown, shiny and epruinose discs. Lobothallia subdiffracta var. rimosa is characterised by its areolate thallus, rimose and pruinose upper surface, lecanorine apothecia and slightly concave to plane, black and pruinose discs. Secondary metabolites were not detected in the two new species nor the new variety. A key is provided for the species of Lobothallia in China.

Based on a combination of morphological, chemical, and phylogenetic analyses, we present a new revision of the lichen genus Pleopsidium in China. Pleopsidium tumidulumsp. nov. and P. corrugatulumsp. nov. are proposed as new species to science, both included in a distinctive clade (clade 1) together with P. gobiense. These three species are characterized by the absence of fatty acids, acaranoic and acarenoic acids, and share similar ecological traits. In contrast, species containing fatty acids, including Pleopsidium flavum, P. chlorophanum, and P. discurrens, constitute a separate clade (clade 2). Fresh specimens of Pleopsidium discurrens were collected from the type locality, Yulong Snow Mountain, and molecular data were generated to confirm the phylogenetic position of the species. Our study additionally reveals substantial morphological variation in this species. New collections and sequences of Pleopsidium gobiense from Hami City, the type locality, are provided, from which a neotype is designated, confirming its phylogenetic position. Differences in morphology, anatomy, chemistry, and ecology among Pleopsidium species from China are discussed. A key and several phylograms are provided.