Three new species of Boletaceae from the Heishiding Nature Reserve in Guangdong Province, China

Abstract

Based on morphological evidence and DNA sequencing, we propose three new species of the basidiomycete family Boletaceae, namely Aureoboletus venustus, Leccinellum onyx, and Pulveroboletus sinensis. The species were collected from the Heishiding Nature Reserve in Guangdong Province, China. The descriptions are illustrated by photographs and line drawings, and comparisons were made with related species. Morphologically, A. venustus is characterized by its mucilaginous pileus with red to reddish orange color, a vivid yellow hymenophore surface, and small ellipsoid basidiospores (7) 7.5–10.5 (12) × 5–6 (7) μm in size. Leccinellum onyx is characterized by its slightly areolating pileus with grayish orange to brownish orange color, a grayish brown to light grayish orange hymenophore surface, short yellowish white tubes, a yellowish white to brownish gray stipe covered with dark brown warts, and small ellipsoid basidiospores with a size of (8) 9–11 (12) × (4) 5–6 μm. Its nucleotide sequence of the internal transcribed spacer (ITS) region is particularly long (1080 bp) in comparison to related species. Pulveroboletus sinensis is characterized by its yellow to vivid yellow pulverulent pileus covered with deep orange to brownish orange conico-pyramidal scales, an appendiculate margin, greenish yellow tubes easily becoming cyanescent upon bruising, a yellow to vivid yellow stipe covered with yellow to brownish orange conico-floccose scales, and small smooth ellipsoid basidiospores with a size of (6) 6.5–8.5 (11) × (4.5) 5–6 (6.5) μm. Phylogenetic analysis of nucleotide sequences of the ITS region and the nuclear large subunit ribosomal RNA gene (nrLSU) provided further evidence that the described mushrooms represent new species.