Two New Species and Two New Records of the Lichen-Forming Fungal Genus Peltula (Ascomycota: Peltulaceae) from China.

Simple Summary: This paper reports on two new species and two new records of the lichen-forming fungal genus Peltula Nyl., highlighting progress in our investigation of Chinese Peltula spp. The external morphology, anatomy, and molecular systematics were comprehensively analyzed to support the species delimitation. The results contribute to the knowledge of species diversity and geographical distributions of Peltula species in China. In this study, two new species, Peltula confusa Q.X. Yang & X.L. Wei, sp. nov., growing in a dry microenvironment within a semi-humid area, and Peltula subpatellata Q.X. Yang & X.L. Wei, sp. nov., occurring in arid and semi-arid regions, are described. In addition, two species, P. polyspora (Tuck.) Wetmore and P. obscuratula (Nyl.) Poelt ex Egea, are recorded for the first time in China. All four species are described based on morphological, anatomical and molecular data. Peltula confusa is characterized by a lighter, brighter, and more yellowish upper surface than other species of this genus, with discs concentrated in the central part of squamules, and a thick lower cortex. Peltula subpatellata can be distinguished from P. patellata (Bagl.) Swinscow & Krog by its non-thickened and sometimes darkened margins and sometimes the presence of peltate squamules. Phylogenetic analysis based on DNA sequences of four loci (ITS, nrSSU, nrLSU, and RPB2) demonstrates the placement of these species within Peltula, and supports current species delimitations. We suggest that the growth substrate should be considered as an additional characteristic for species delimitation. [ABSTRACT FROM AUTHOR]