The aim of this study was to characterize the molecular relationship, origin and historical biogeography of the species in important brown rot fungal genus Laetiporus from East Asia, Europe, Pan-America, Hawaii and South Africa. We used six genetic markers to estimate a genus-level phylogeny including (1) the internal transcribed spacer (ITS), (2) nuclear large subunit rDNA (nrLSU), (3) nuclear small subunit rDNA (nrSSU), (4) translation elongation factor 1-α (EF-1α), (5) DNA-directed RNA polymerase II subunit 2 (RPB2), and (6) mitochondrial small subunit rDNA (mtSSU). Results of multi-locus phylogenetic analyses show clade support for at least seventeen species-level lineages including two new Laetiporus in China. Molecular dating using BEAST estimated the present crown group diverged approximately 20.16 million years ago (Mya) in the early Miocene. Biogeographic analyses using RASP indicated that Laetiporus most likely originated in temperate zones with East Asia and North America having the highest probability (48%) of being the ancestral area. Four intercontinental dispersal routes and a possible concealed dispersal route were established for the first time.
Two new Russula species, R. subbrevipes and R. callainomarginis, from China are described based on morphological and molecular characteristics. Russula subbrevipes has thus far only been found in southwestern China at altitudes of higher than 3400 m and is characterized by a yellow ochre pileal surface, glabrous or tomentose stipe, fruity odor, subglobose to ellipsoid basidiospores, isolated or partially connected warts and pleurocystidia with a cap appendage. Russula callainomarginis is characterized by a cream to white pileus, light turquoise lamellae margin, spongy stipe, light turquoise zone on the top of the stipe, pungent odor, globose to ellipsoid basidiospores and dominant isolated warts. The phylogenetic tree of Russula was constructed with multi-gene sequences, including the internal transcribed spacer regions (ITS), the ribosomal large subunit (nrLSU), the small subunit of the mitochondrial rRNA gene (mtSSU) and the second largest subunit of RNA polymerase II (RPB2). The results show that both R. subbrevipes and R. callainomarginis represent new lineages in Russula subg. Brevipes. Description and illustration of the two new species are presented.
Laetiporus is a cosmopolitan genus of brown rot fungi. In this study, L.medogensis and L.xinjiangensis are described as new species from western China, based on morphological and molecular evidence. L.medogensis has only been found on gymnosperms so far and is distinguished by pinkish-buff to clay-buff pileal surface and buff-yellow pore surface, azonate to faintly zonate pileus and ellipsoid to ovoid basidiospores (5–6.2 × 4.2–5.2 μm). L.xinjiangensis is found on angiosperms and is characterised by pale-buff to clay-pink pileal surface, cream to light yellow pore surface, azonate to faintly zonate pileus, large pores (2–3 per mm) and small basidiospores (4.5–5 × 3–4.2 μm). The phylogeny of Laetiporus is reconstructed with multi-gene sequences including the internal transcribed spacer regions (ITS), the large subunit (nrLSU) and small subunit (nrSSU) of the nuclear ribosomal RNA gene, the small subunit of the mitochondrial rRNA gene (mtSSU), the translation elongation factor 1-α gene (EF-1α) and the second subunit of RNA polymerase II (RPB2). The results show that L.medogensis and L.xinjiangensis formed two distinct lineages belonging to Laetiporus. Illustrated descriptions of the two new species are presented. An identification key to species of L.sulphureus complex is provided.
Two new species of Russula subg. Heterophyllidia from Guangdong Province of China were described and illustrated based on morphological characters, and their identity supported by molecular phylogeny. R. luofuensis is morphologically characterized by a grayish yellow to brownish orange pileus center with a purplish gray to grayish magenta margin, a surface that is cracked and broken into small golden-brown patches, subglobose to broadly ellipsoid basidiospores with warts fused in short or long chains and a suprapellis composed of hyphal extremities with inflated, ellipsoid or globose cells and attenuated terminal cell. R. subbubalina is distinguished by the blanched almond to dark salmon pileus that is cracked with age, subglobose to broadly ellipsoid basidiospores with wart fused in short or long chains and frequently connected by line connections, a suprapellis with hyphal ends composed of inflated or ellipsoid cells and attenuated terminal cell, and pileocystidia that are mainly clavate and sometimes with round or ellipsoid appendage. The phylogenetic analyses based on ITS-nrLSU-mtSSU-TEF1 dataset were performed using maximum likelihood and Bayesian analysis. In terms of morphological features and molecular data, the former species belongs to subsect. Virescentinae, whereas the latter comes under subsect. Heterophyllinae.
Two new species of Russula are described and illustrated in this paper. Russula clavulus is recognised by a pale yellow pileus centre, white margin with tuberculate striation, white to pale lamellae with small pale yellow spots, white to light yellow spore print, subglobose to broadly ellipsoid spores with short or long ridges and hymenial cystidia on lamellae sides that are mainly subclavate or fusiform. Russula multilamellula is morphologically characterised by the brownish orange to hazel pileus centre and satin white to yellowish-white margin with brownish tinge, lamellulae that are usually irregular in length and often anastomosing with lamellae, subglobose to broadly ellipsoid spores with short or long ridges and clavate hymenial cystidia. The combination of morphological features and multigene phylogenetic analyses of ITS-nrLSU-RPB2-mtSSU data indicated that these two new taxa belong to Russula subg. Heterophyllidia sect. Ingratae.