Three New Species and a New Record of the Lichen Genus Peltula (Peltulaceae) from Helan Mountain in China

In this study, a systematic taxonomic analysis was carried out on the lichen genus <i>Peltula</i>, collected from Helan Mountain in China; three new species (<i>Peltula helanense</i>, <i>P. overlappine</i>, and <i>P. reticulata</i>) and a new record (<i>P. crispatula</i> (Nyl.) Egea) for China were identified. Four species were identified by morph-anatomical, chemical, and phylogenetic analyses by combining two gene loci (ITS and LSU). <i>Peltula helanense</i> is with tiny individual thalli up to 1mm, attached by creamy-white cylindrical rhizoids and apothecia filling the whole squamule. <i>Peltula overlappine</i> is characterized by thallus squamulose forming rosette-shaped patches and squamules with distinctive thickened margins. <i>Peltula reticulata</i> is characterized by brownish brown thallus and squamules with densely reticulate upper surface. <i>P. crispatula</i> is characterized by irregular squamules attached to a tuft of hyphae. The four species are described in detail, compared, and discussed with similar species, and images of morpho-anatomical structures of the four species are also provided. Moreover, a key to the species of <i>Peltula</i> from Helan Mountain is provided. The results enrich the data of the genus <i>Peltula</i> and also indicate that the rich diversity of lichen species in Helan Mountain is worthy of in-depth study.