Morphological and molecular evidence reveal two new species of Sutorius (Boletaceae, Basidiomycota) from Guizhou Province, China

Sutorius is a genus within the family Boletaceae, typically characterised by chocolate-brown to reddish-brown or slightly purplish colouration, finely scaly stems and reddish-brown spore deposits. Although numerous species of this genus have been reported from India and northern to north-eastern Thailand, its species diversity remains insufficiently explored. During an extensive survey on diversity of boletes in Zunyi City, Guizhou Province, China, this study identified two new Sutorius species, based on morphological and multi-locus (nrLSU, nrITS, TEF 1 - α and RPB 2) phylogenetic analyses and they were assigned as S. yuxiensis and S. rubropurpureus.

Sutorius yuxiensis is morphologically characterised by a yellowish-brown pileus with densely arranged pores, giving the surface an irregular appearance, along with a pale purplish-grey colouration. Sutorius rubropurpureus is morphologically characterised by a purplish-red to purplish-grey pileus, the pore surface is purplish-red to reddish-brown in colour and the presence of pleurocystidia. S. yuxiensis is phylogenetically close to S. obscuripellis and S. ubonensis and forms an independent lineage.

S. rubropurpureus clusters with S. rubinus and related congeners. Detailed descriptions, illustrations, phylogenetic analyses and comparisons with closelyrelated taxa are provided to support the recognition of these two novel species.