Large Subunit Ribosomal Sequences Research Articles

A hidden basidiolichen rediscovered: Omphalina oreades is a separate species in the genus Lichenomphalia (Basidiomycota: Agaricales: Hygrophoraceae)

AbstractMolecular studies have shown the type collection of Omphalina oreades to be conspecific with a small brown basidiolichen from the Appalachian range in Newfoundland, both with 4-spored basidia. Two sequences deposited in GenBank, originally identified as O. grisella, fell in the same clade. Sequences of the type collection of Omphalia grisella, with 2-spored basidia, formed a sister clade together with two GenBank deposits, one identified as O. grisella and the other as Omphalina velutina. Omphalina oreades is recombined here as Lichenomphalia oreades comb. nov., and the species redescribed and illustrated. Sequences of the internal transcribed spacer regions of nuclear ribosomal DNA (ITS rDNA) from the algae associated with two collections of L. oreades fell within a highly supported clade with members of an undetermined species of Coccomyxa. The most abundant algal ribosomal large subunit sequence from granules at the base of a different collection matched GenBank sequences identified as Chloroidium ellipsoideum, which is probably either a free-living algal species or a partner to a species of Trapeliopsis. The second most abundant sequence matched Coccomyxa subellipsoidea and is the most likely photobiont of L. oreades. Further studies are required to elucidate the relationship of L. velutina to these taxa.

New records of Cantharellus species from the northwestern Himalayas of India

This study investigated several collections of the genus Cantharellus (Cantharellaceae) from the northwestern Himalayas, India, on the basis of morphology and molecular data. Phylogenetic relationships and species limits were investigated by using nuclear ribosomal large subunit sequences (LSU). We recognized 13 species: Cantharellus appalachiensis Petersen, C. cibarius Fries, C. lateritius (Berk) Singer, C. miniatescens Heinem, C. minor Peck, C. pseudoformosus and seven species, C. applanatus sp. nov., C. elongatipes sp. nov., C. fibrillosus sp. nov., C. himalayensis sp. nov., C. indicus sp. nov., C. natarajanii sp. nov., and C. umbonatus sp. nov., as new to science. All these species are described and their taxonomy and ecology are discussed. In addition, a key is provided to all the recognized species. The phylogenetic analysis recovered 10 major supported clades of Cantharellus species.

A new lineage of lichenized basidiomycetes inferred from a two‐gene phylogeny: The Lepidostromataceae with three species from the tropics

The lichen habit has apparently evolved independently in at least five major clades of mushroom-forming basidiomycetes (Agaricomycetes). Tracing the origin of lichenization in these groups depends on a clearer understanding of the phylogenetic relationships of basidiolichens to other fungi. We describe here a new family of basidiolichens made up of tropical, soil-inhabiting fungi that form lichenized, scale-like squamules and erect, coral-like fruiting structures. These structures are common to two basidiolichen genera, Multiclavula and Lepidostroma. Molecular studies have confirmed the phylogenetic position of Multiclavula species in the Cantharellales, but Lepidostroma species have never been sequenced. We obtained nuclear small and large subunit ribosomal sequences from specimens of L. calocerum collected in Costa Rica and Mexico and also from specimens of two Multiclavula spp. recently described from Rwanda. The phylogenetic placement of these fungi within the Agaricomycetes was investigated using likelihood and Bayesian analyses. Our results indicate that L. calocerum and the Rwandan species form a natural group unrelated to Multiclavula and sister to the Atheliales, members of which are neither lichen-forming nor clavarioid. The independent evolution of morphologically similar forms in so many groups of basidiomycetes is a remarkable example of convergence, indicating similar pathways to lichenization in these fungi.

Remarkable nutritional diversity of basidiomycetes in the Corticiales, including a new foliicolous species ofMarchandiomyces(anamorphic Basidiomycota, Corticiaceae) from Australia

Fungi in the basidiomycete order Corticiales are remarkably diverse nutritionally, including a variety of saprotrophs, plant and fungal pathogens, and lichen-forming fungi. Tracing the origin of this diversity depends on a clearer understanding of the phylogenetic relationships of fungi in the order. One of its core members is the genus Marchandiomyces, originally established for lichen pathogens that form orange or coral bulbils. We describe here a new species in the genus, M. marsonii sp. nov., which is unusual in its appearance, habit, and geographic provenance. It is foliicolous on leaves of Pandanus (screw pines, Pandanaceae) and produces flattened, coral bulbils resembling apothecia of the ascomycete genus Orbilia. It is also the first member of the genus to be collected from Australia. An isolate of the new fungus and several additional cultures of related plant pathogenic fungi were obtained and investigated phylogenetically using parsimony, likelihood, and Bayesian analyses of nuclear small and large subunit ribosomal sequences. Our phylogeny makes clear that Marchandiomyces species and their close relatives contribute significantly to the ecological diversity of the Corticiales and that this diversity is derived mainly from lignicolous ancestors.