Morphological Characteristics and Molecular Evidence Reveal four New Species of Russula subg. Brevipedum from China

In this study, four new species of Russula subg. Brevipedum collected from China are described based on morphological characteristics and molecular evidence. Russula brevispora has a white body whose whole parts often stain brownish-orange or grayish-orange, extremely crowded lamellae with the presence of lamellulae, basidiospores with low warts and an inamyloid suprahilar spot, and clavate or lageniform hymenial cystidia often with a papillary or submoniliform appendage. Russula flavescens is characterized by a white pileus often turning yellowish brown when touched, white lamellae turning brown or light orange, basidiospores with an inamyloid suprahilar spot, and fusiform hymenial cystidia often with an appendage. Russula longicollis is morphologically characterized by a white pileus, turning grayish orange when bruised, white lamellae turning pale yellow when bruised, basidiospores with isolated warts and an amyloid suprahilar spot, and fusiform hymenial cystidia usually with a long appendage. Russula pseudojaponica has a yellowish-brown pileus center, yellowish lamellae unchanging when bruised, basidiospores with low warts and an inamyloid suprahilar spot, clavate hymenial cystidia often with a papillary appendage, and clavate pileocystidia with granulose contents. Phylogenetic analyses showed that R. flavescens, R. brevispora, and R. pseudojaponica are members of the subsect. Pallidosporinae, whereas R. longicollis belongs to subsect. Lactarioideae, and is somewhat related to R. leucocarpa.