Guyanagaster, a New Wood-Decaying Sequestrate Fungal Genus Related to Armillaria (Physalacriaceae, Agaricales, Basidiomycota)

Loading...
Thumbnail Image

Date

2010

Journal Title

Journal ISSN

Volume Title

Repository Usage Stats

471
views
469
downloads

Citation Stats

Abstract

Premise of the study : Sequestrate basidiomycete fungi (e. g. "gasteromycetes") have foregone ballistospory and evolved alternative, often elaborate mechanisms of basidiospore dispersal with highly altered basidioma morphology. Sequestrate fungi have independently evolved in numerous Agaricomycete lineages, confounding taxonomic arrangements of these fungi for decades. Understanding the multiple origins and taxonomic affinities of sequestrate fungi provides insight into the evolutionary forces that can drastically alter basidioma morphology. In the neotropical rainforests of the Guiana Shield, we encountered a remarkable sequestrate fungus fruiting directly on decaying hardwood roots. The fungus 'singular combination of traits include a wood-decaying habit; black, verrucose peridium; reduced stipe; and gelatinized basidiospore mass. Methods : Guyanagaster necrorhiza gen. et sp. nov. is described. Macro-and micromorphological characters were assessed and compared to most similar taxa. To determine the phylogenetic affinities of the fungus, DNA sequence data were obtained for the 18S, ITS, and 28S rDNA, RBP2, and EF1 alpha regions and subjected to single-and multi-gene analyses. DNA sequences from fungal vegetative organs growing on decaying woody roots confirmed the wood-inhabiting lifestyle of Guyanagaster. Key results : Guyanagaster is morphologically unique among sequestrate fungi worldwide. Phylogenetic evidence places Guyanagaster in close relation to the wood-decaying mushroom genus Armillaria in the Physalacriaceae (Agaricales, Agaricomycetes, Basidiomycota). Conclusions : Guyanagaster represents an independently evolved sequestrate form within the Physalacriaceae. Although molecular data confirm that Guyanagaster is closely related to Armillaria, the unusual features of this fungus suggest a case of radically divergent morphological evolution.

Department

Description

Provenance

Citation

Henkel,Terry W.;Smith,Matthew E.;Aime,M. Catherine. 2010. Guyanagaster, a New Wood-Decaying Sequestrate Fungal Genus Related to Armillaria (Physalacriaceae, Agaricales, Basidiomycota). American Journal of Botany 97(9): 1474-1484.

Published Version (Please cite this version)

10.3732/ajb.1000097


Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.