Phylogenetic overview of the Boletineae

The generic and sub-generic relationships in the Boletineae (Boletales) were studied using nuclear large subunit (nuc-lsu), translation elongation factor 1-alpha (tef1), and DNA directed RNA polymerase largest subunit (RPB1). The Boletineae, with the exclusion of Hydnomerulius pinastri, was strongly supported and the status of the families Boletaceae and Paxillaceae is discussed. Members of the genus Boletus are found throughout the phylogeny, with the majority not closely related to the type species, Boletus edulis. Many of the traditional, morphologically defined genera are not supported as monophyletic and additional sampling and taxonomic revisions are needed. The majority of the Boletineae are confirmed or putatively ectomycorrhizal (ECM), but two putatively mycoparasitic lineages (one lineage of Buchwaldoboletus lignicola and Chalciporus piperatus and the second Pseudoboletus parasiticus) are strongly supported.

Sutorius: a new genus for Boletus eximius

Sutorius is described as a new genus of Boletaceae to accommodate Boletus robustus originally named illegitimately by C.C. Frost from eastern North America. The legitimate name, Boletus eximius, provided by C.H. Peck, has been used since for a dark purple to chocolate brown bolete with finely scaly stipe and reddish brown spore deposit. This iconic taxon has been documented on five continents. Despite the straightforward species identification from morphology, the interpretation of stipe macro-morphology and spore color has led to equivocal generic placement. Phylogenetic analyses of genes encoding large subunit rRNA and translation elongation factor 1α confirm Sutorius as a unique generic lineage in the Boletaceae. Two species are recognized based on multiple accessions: S. eximius, represented by collections from North America, Costa Rica, Guyana, Indonesia and Japan (molecular data are lacking for only the Guyanan and Japanese material); and S. australiensis, represented by material from Queensland, Australia. Additional collections from Zambia and Thailand represent independent lineages, but sampling is insufficient to describe new species for these entities.

Tylopilus orsonianus sp. nov. and Tylopilus eximius from Guyana

Tylopilus orsonianus sp. nov. and Tylopilus eximius (Boletaceae, Basidiomycota) are described for the first time from the Pakaraima Mountains of Guyana. Both boletes occur in forests dominated by ectomycorrhizal trees in the genus Dicymbe (Caesalpiniaceae). A key to Tylopilus species distinguishes those known to occur in Guyana.

New Cortinarius species associated with Quercus and Comarostaphylis in Costa Rica

Ten new species of Cortinarius are described from Costa Rican neotropical montane forests based on morphological and molecular phylogenetic data. Morphological features of the basidiomes and nuclear rDNA sequence analyses place these species in the following clades: Anomali ( Cortinarius sericeolazulinus ), Cotoneus ( Cortinarius aureopigmentatus ), Limonii ( Cortinarius aurantiobrunneus ), Lustrati ( Cortinarius comarostaphylii , Cortinarius comparioides , Cortinarius ovreboi ), Myxacium ( Cortinarius costaricensis ), and Telamonia ( Cortinarius carranzae , Cortinarius quercoarmillatus , Cortinarius savegrensis ). Species delimitations, diagnostic characters, sequence pair wise comparisons, and affinities to closely related species are included for each species. These Cortinarii occur with several species of Quercus with the exception of C. comarostaphylii, which is associated with Comarostaphylis (Ericaceae) in the páramo and in mixed forests with Quercus and Comarostaphylis.

A new genus of Boletaceae from eastern North America

Bothia is described as a new genus in the Boletaceae based on Boletinus castanellus described by C.H. Peck from eastern North America. A widespread, occasionally encountered taxon, Bothia castanella possesses a combination of macro- and microscopic features that has prompted past placement in seven different genera. Yet, as a species it is readily recognizable with its chestnut brown, dry pileus, decurrent, pale brown hymenophore with radially elongated tubes, a short, sometimes eccentric, exannulate stipe, yellow brown spore deposit and constant association with Quercus. Phylogenetic analyses of large subunit rDNA and BLAST searches using the ITS region confirm the placement of B. castanella as a unique generic lineage in the Boletaceae.

Morphological and molecular evidence supporting an arbutoid mycorrhizal relationship in the Costa Rican páramo

This study examines evidence for a particular arbutoid mycorrhizal interaction in páramo, a high-altitude neotropical ecosystem important in hydrological regulation but poorly known in terms of its fungal communities. Comarostaphylis arbutoides Lindley (Ericaceae) often forms dense thickets in Central American páramo habitats. Based on phylogenetic classification, it has been suggested that C. arbutoides forms arbutoid mycorrhizae with diverse Basidiomycetes and Ascomycetes; however, this assumption has not previously been confirmed. Based on field data, we hypothesized an arbutoid mycorrhizal association between C. arbutoides and the recently described bolete Leccinum monticola Halling & G.M. Mueller; in this study, we applied a rigorous approach using anatomical and molecular data to examine evidence for such an association. We examined root samples collected beneath L. monticola basidiomes for mycorrhizal structures, and we also compared rDNA internal transcribed spacer (ITS) sequences between mycorrhizal root tips and leaf or basidiome material of the suspected symbionts. Root cross sections showed a thin hyphal sheath and intracellular hyphal coils typical of arbutoid mycorrhizae. DNA sequence comparisons confirmed the identity of C. arbutoides and L. monticola as the mycorrhizal symbionts. In addition, this paper provides additional evidence for the widespread presence of minisatellite-like inserts in the ITS1 spacer in Leccinum species (including a characterization of the insert in L. monticola) and reports the use of an angiosperm-specific ITS primer pair useful for amplifying plant DNA from mycorrhizal roots without co-amplifying fungal DNA.

Leccinum (boletaceae) in costa rica

Complete descriptions, illustrations, distributions and a key to species are provided for the eight known Costa Rican species of Leccinum. Leccinum tablense is newly described from oak forests, and Leccinum monticola is newly described from the páramo and adjacent timberline oak forests where it appears to be associated with Comarostaphylis arbutoides-a member of the Ericaceae. All are compared to similar taxa.