title: A molecular and morphological re-examination of the generic limits of truffles in the tarzetta-geopyxis lineage - Densocarpa, Hydnocystis, and Paurocotylis.
abstract: Truffle species within the /tarzetta-geopyxis lineage share smooth, globose, hyaline spores, but differ in the amount of convolution of hymenia in ascomata. The relationships among truffle species in this lineage have historically been confused. Phylogenetic analyses of the ITS and 28S nuclear ribosomal DNA from recently collected members of the /tarzetta-geopyxis lineage from Asia, Austral Asia, North America, and South America prompted a reinvestigation of species and generic limits in the truffle genera Hydnocystis, Paurocotylis, and Stephensia. Our analyses support emendations of Hydnocystis and Paurocotylis, abandonment of Stephensia and the resurrection of the genus Densocarpa. Nomenclatural changes include the transfer of Stephensia bombycina to Hydnocystis, the transfer of Hydnocystis singeri and Stephensia bynumii to Paurocotylis, the reinstatement of Densocarpa for Stephensia shanori and transfer of Stephensia crocea to Densocarpa. This is the first detection of the genus Paurocotylis in the Americas. We describe three new species, Hydnocystis transitoria from North America, Paurocotylis patagonica from South America, and Paurocotylis watlingii from Australia. Our work highlights the unexplored diversity, morphological plasticity, and remaining taxonomic problems among truffles in the /tarzetta-geopyxis lineage.
authors.affiliation: Department of Plant Biology, University of Minnesota, 1445 Gortner Avenue, St. Paul, MN 55108, USA; Department of Plant Pathology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Leticia M
authors.initials: LM
authors.lastname: Kumar
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: Instituto Multidisciplinario de Biología Vegetal (CONICET), Universidad Nacional de Córdoba, 5000, Argentina.
authors.forename: Eduardo R
authors.initials: ER
authors.lastname: Nouhra
authors.affiliation: Kanagawa Prefectural Museum of Natural History, 499 Iryuda, Odawara-shi, Kanagawa 250-0031, Japan.
authors.forename: Takamichi
authors.initials: T
authors.lastname: Orihara
authors.affiliation: Biota Gestión y Consultorías Ambientales Ltda., Miguel Claro 1224, Providencia, Santiago 7500000, Chile.
authors.forename: Pablo
authors.initials: P
authors.lastname: Sandoval Leiva
authors.affiliation: Farlow Herbarium, Harvard University, 22 Divinity Ave., Cambridge, MA 02138, USA.
authors.forename: Donald H
authors.initials: DH
authors.lastname: Pfister
authors.affiliation: Department of Plant Biology, University of Minnesota, 1445 Gortner Avenue, St. Paul, MN 55108, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: McLaughlin
authors.affiliation: Department of Forest Ecosystems and Society, Oregon State University, Corvalis, OR 97331, USA.
authors.forename: James M
authors.initials: JM
authors.lastname: Trappe
authors.affiliation: Department of Plant Biology, University of Minnesota, 1445 Gortner Avenue, St. Paul, MN 55108, USA; Department of Plant Pathology, University of Florida, Gainesville, FL 32611, USA. Electronic address: rosanne.healy@gmail.com.
authors.forename: Rosanne A
authors.initials: RA
authors.lastname: Healy
mesh_terms: D000569:Americas; D001203:Ascomycota / Q000145:classification* / Q000166:cytology / Q000235:genetics; D001208:Asia; D044362:Australasia; D016000:Cluster Analysis; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D008853:Microscopy; D010802:Phylogeny; D012339:RNA, Ribosomal, 28S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012339:RNA, Ribosomal, 28S
keywords: Hypogeous fungi; Pezizales anamorphs; Truffle evolution