title: Guyanagarika, a new ectomycorrhizal genus of Agaricales from the Neotropics.
abstract: A new genus and three new species of Agaricales are described from the Pakaraima Mountains of Guyana in the central Guiana Shield. All three of these new species fruit on the ground in association with species of the ectomycorrhizal (ECM) tree genus Dicymbe (Fabaceae subfam. Caesalpinioideae) and one species has been shown to form ectomycorrhizas. Multi-locus molecular phylogenetic analyses place Guyanagarika gen. nov. within the Catathelasma clade, a lineage in the suborder Tricholomatineae of the Agaricales. We formally recognize this 'Catathelasma clade' as an expanded family Catathelasmataceae that includes the genera Callistosporium, Catathelasma, Guyanagarika, Macrocybe, Pleurocollybia, and Pseudolaccaria. Within the Catathelasmataceae, Catathelasma and Guyanagarika represent independent origins of the ectomycorrhizal habit. Guyanagarika is the first documented case of an ECM Agaricales genus known only from the Neotropics.
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA. Electronic address: MSanchezGarcia@clarku.edu.
authors.forename: Marisol
authors.initials: M
authors.lastname: Sánchez-García
authors.affiliation: Department of Biological Sciences, Humboldt State University, Arcata, CA 95521, USA.
authors.forename: Terry W
authors.initials: TW
authors.lastname: Henkel
authors.affiliation: Department of Botany & Plant Pathology, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Mary Catherine
authors.initials: MC
authors.lastname: Aime
authors.affiliation: Department of Plant Pathology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Smith
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA.
authors.forename: Patrick Brandon
authors.initials: PB
authors.lastname: Matheny
mesh_terms: D000363:Agaricales / Q000145:classification* / Q000302:isolation & purification*; D007887:Fabaceae / Q000382:microbiology*; D006172:Guyana; D058885:Multilocus Sequence Typing; D038821:Mycorrhizae / Q000145:classification* / Q000302:isolation & purification*; D010802:Phylogeny
keywords: Basidiomycota; Cryptic species; Dicymbe; Fungal diversity; Systematics