Three new species of Sanguinoderma (Ganodermataceae, Basidiomycota) from Southwest China revealed by morphology and phylogenetic analysis

<i>Sanguinoderma</i> (<i>Ganodermataceae</i>) is an economically signaificant genus with notable medicinal value. A key diagnostic characteristic is the reddening of pores upon bruising. The genus is mainly distributed in tropical and subtropical regions, where it grows on the surface of humus or on decaying tree trunks. In this study, during a survey of macrofungi in southwestern China, seven <i>Sanguinoderma</i> specimens were collected. Based on morphological characteristics and phylogenetic analysis combined with six-loci of the internal transcribed spacer (ITS), nuclear ribosomal large subunit (LSU), RNA polymerase II second largest subunit (<i>rpb</i>2), translation elongation factor 1-alpha (<i>tef</i>1-α), mitochondrial small subunit (mtSSU), and nuclear small subunit (nSSU), three new species of <i>Sanguinoderma</i> are identified and introduced: <i>Sanguinoderma aurantiacus, S. bambusae</i> and <i>S. niger</i>. <i>Sanguinoderma aurantiacus</i> is characterized by a glabrous pileus with alternating concentric zones that range from black to dark orange, margins are dark red, acute, wavy and slightly incurved when dry, the pileus context is thin, light grayish and corky, and basidiospores are ellipsoid to subglobose ((10.0–13.5) × (8.9–10.9) μm). <i>Sanguinoderma bambusae</i> grows on the forest floor in bamboo forests, it has an oval to subcircular, glabrous pileus with a lacerated margin resembling sparse petals, the pores are small (6–9 per mm) and oval to circular, basidiospores are broadly ellipsoid ((10.1–14.4) × (8.6–11.6) µm). <i>Sanguinoderma niger</i> is characterized by black to dark grayish orange pileus, and its context is soft and corky, turning grayish orange when dry, cystidia are oblong to ovoid, and basidiospores are subglobose to globose ((8.9–12.6) × (8.0–10.0) µm). This study has enriched the diversity of the <i>Sanguinoderma</i> species.