Marcelo A. Sulzbacher

Starting from scratch: Evolution of the lichen thallus in the basidiolichen Dictyonema (Agaricales: Hygrophoraceae).

Phylogenetic studies indicate that the basidiolichen genus Dictyonema s.lat., often thought to represent only a single genus with few species, includes several well-supported genus-level clades, all of which form associations with a unique lineage of obligately lichenized cyanobacteria (Rhizonema). In an attempt to elucidate the evolution and genus- and species-level diversification in Dictyonema s.lat., we generated 68 new sequences of the nuclear large subunit rDNA (nuLSU), the internal transcribed spacer (ITS), and the RNA polymerase II subunit (RPB2), for 29 species-level lineages representing all major clades of Dictyonema s.lat. and most of the species currently known. The multilocus phylogeny obtained via maximum likelihood and Bayesian approaches indicates the presence of five genus-level groups: a basal clade, Cyphellostereum, that is sister to the rest of the species, a paraphyletic grade representing Dictyonema s.str., and three clades representing the genera Acantholichen, Cora, and Corella. To determine the evolutionary transformations of the lichenized thallus in the group, ancestral character state reconstruction was done using six characters (lichenisation, thallus type, cortex type, hyphal sheath and haustorial type, photobiont morphology, and basidiocarp type). Our analysis indicates a progressive development of the lichenized thallus from loosely organized filamentous crusts with separate, cyphelloid basidiocarps in Cyphellostereum, to filamentous crusts with derived hyphal sheath and cyphelloid-stereoid basidiocarps partially incorporated into the lichen thallus in Dictyonema, to squamulose-foliose thalli with corticioid basidiocarps entirely supported by the lichen thallus in Cora. These results indicate a remarkable evolutionary integration of lichenized and reproductive tissues in Dictyonema s.lat., supporting the hypothesis that, at least in this case, lichenized thalli may have evolved from reproductive structures in their nonlichenized ancestors.

Unexpected discovery of a novel basidiolichen in the threatened Caatinga biome of northeastern Brazil

Abstract Many of the species living on our planet remain undiscovered, among these over one million Fungi. One approach to account for undescribed species is the search in unusual habitats. Here we report on the unexpected finding of a new species of Lepidostroma (Atheliales: Lepidostromataceae) from the semi-arid Caatinga biome in northeastern Brazil. It is only the fifth species of this enigmatic genus and only the third from the Neotropics, and the fourth species to be described within the past four years. DNA was extracted and the ITS and nuLSU partitions of the nuclear rDNA were sequenced. A phylogenetic tree was computed under a maximum likelihood framework using an alignment of selected Basidiomycota (Atheliales, Agaricales, Boletales, Russulales, Cantharellales). The new species differs from other species in the genus by the crustose rather than squamulose thallus. Molecular sequence data place the species as unsupported sister to Lepidostroma akagerae. The crustose thallus resembles that of Multiclavula species, which are phylogenetically unrelated. This study underlines that novel lichenized Fungi can be discovered in unusual habitats. The Caatinga vegetation is to a large extent threatened by habitat destruction and the discovery of such an unusual species underlines the importance of this unique biome for conserving diversity in tropical South America. Systematically, the new species is relevant because it represents the only species of Lepidostroma with a crustose, Multiclavula-like thallus, presenting a striking example of parallel evolution in lichenized Basidiomycota.

Molecular and morphological analyses confirm Rhizopogon verii as a widely distributed ectomycorrhizal false truffle in Europe, and its presence in South America

The genus Rhizopogon includes species with hypogeous or subepigeus habit, forming ectomycorrhizae with naturally occurring or planted pines (Pinaceae). Species of the genus Rhizopogon can be distinguished easily from the other hypogeous basidiomycetes by their lacunose gleba without columella and their smooth elliptical spores; however, the limit between species is not always easy to establish. Rhizopogon luteolus, the type species of the genus, has been considered one of the species that are more abundant in Europe, as well as it has been cited in pine plantation of North and South America, different parts of Africa, Australia, and New Zealand. However, in this study, based on molecular analyses of the ITS nuclear ribosomal DNA (nrDNA) sequences (19 new sequences; 37 sequences from GenBank/UNITE, including those from type specimens), we prove that many GenBank sequences under R. luteolus were misidentified and correspond to Rhizopogon verii, a species described from Tunisia. Also, we confirm that basidiomes and ectomycorrhizae recently collected in Germany under Pinus sylvestris, as well as specimens from South of Brazil under Pinus taeda belong to R. verii. Thanks to the numerous ectomycorrhizal tips collected in Germany, a complete description of R. verii/P. sylvestris ectomycorrhiza is provided. Moreover, since in this paper the presence of R. verii in South America is here reported for the first time, a short description of basidiomes collected in Brazil, compared with collections located in different European herbaria, is included.

Sebacina aureomagnifica , a new heterobasidiomycete from the Atlantic Forest of northeast Brazil

Sebacina aureomagnifica is described as a new species based on collections from the Atlantic Forest of Paraíba and Rio Grande do Norte, in northeastern Brazil, and is molecularly attributed to the genus Sebacina based on its ribosomal DNA sequence. A striking feature of this newly described fungus is the production of erect, gelatinous yellow basidiomes growing epigeously.

Restingomyces, a new sequestrate genus from the Brazilian Atlantic rainforest that is phylogenetically related to early-diverging taxa in Trappeaceae (Phallales)

Restingomyces reticulatus gen. et sp. nov. is a recently discovered false truffle species from Atlantic “restinga” rainforest in northeastern Brazil. Molecular and morphological characters separate this new sequestrate species from other described taxa in the order Phallales (Phallomycetidae, Basidiomycota). In our phylogenetic analysis based on nuc 28S rDNA and atp6, R. reticulatus forms a sister clade to Trappea darkeri and Phallobata alba, with the three taxa forming the earliest diverging lineage within Phallales. Morphological and molecular data warrant the recognition of the new genus and species, described here, and we also amend the taxonomic description for the family Trappeaceae.