title: Cercopemyces crocodilinus, a new genus and species related to Ripartitella, is described from North America.
abstract: Cercopemyces is described as a new genus based on collections of a newly discovered agaricoid species from the arid Cercocarpus forests of Utah and Colorado. The new genus is near Ripartitella and Cystodermella based on nLSU, rpb1 and ITS molecular sequences but distinctly different from these taxa. The ornamented basidiospores and inflated cells in the scales of the pileus surface of Cercopemyces indicate a close relationship to some species of Ripartitella, and the molecular analyses support the sister group relationship. Morphologically Cercopemyces crocodilinus is reminiscent of the genus Amanita in the field, but the inamyloid, cyanophilic, ornamented basidiospores and lack of acrophysalidic hyphae in the trama indicate otherwise. A rare eastern USA species, Ripartitella ponderosa, is transferred to Cercopemyces based on morphological and molecular data.
authors.affiliation: Department of Biological Sciences, 340 Bowers Hall, Graham Ave., PO Box 2000, State University of New York - College at Cortland, Cortland, New York 13045 tim.baroni@cortland.edu.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Baroni
authors.affiliation: Biology Department, Utah State University, 5305 Old Main Hill, Logan, Utah 84322.
authors.forename: Bradley R
authors.initials: BR
authors.lastname: Kropp
authors.affiliation: Sam Mitchel Herbarium of Fungi, Denver Botanical Gardens, 909 York Street, Denver, Colorado 80206.
authors.forename: Vera S
authors.initials: VS
authors.lastname: Evenson
authors.affiliation: Felsenweg 66, CH-4123 Allschwil, Switzerland.
authors.forename: Markus
authors.initials: M
authors.lastname: Wilhelm
mesh_terms: D000363:Agaricales / Q000145:classification* / Q000235:genetics / Q000648:ultrastructure; D001483:Base Sequence; D003120:Colorado; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics; D025301:Hyphae; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D016533:Mycological Typing Techniques; D010802:Phylogeny; D012319:RNA Polymerase II / Q000235:genetics; D027824:Rosaceae / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D013172:Spores, Fungal; D014197:Trees; D014589:Utah
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D005656:Fungal Proteins; D012319:RNA Polymerase II
keywords: Cercocarpus; Cystoderma; Cystodermella; Great Basin; ITS; nLSU; new combination; phylogenetics; rpb1