The Clavariaceae is a poorly studied family of mushroom-forming fungi and the earliest evolutionary branch in the order Agaricales, the most diverse group of mushroom-forming fungi in the Agaricomycotina. The family is characterized by a high diversity of morphological and ecological features, including roles as decomposers and plant root symbionts. A robust phylogeny coupled with evolutionary analyses should yield insights into patterns that have led to its high diversity. The products of this research will include a molecular-based phylogeny, with which ecological and trait evolution analyses will be performed. Additionally, identification and description of novel species and a taxonomic revision of the family are planned. The research will also contribute to the first modern floristic treatment of the family in the United States.

Results of this research will be presented at professional and amateur scientific meetings. A molecular reference dataset of known species of Clavariaceae will be produced that will aid identification of DNA sequences obtained from soil and other environmental samples. The proposed collaborative effort involves researchers in Europe and Australia and contributions from domestic and international herbaria and amateur naturalists. Several undergraduates will be trained in aspects of molecular biology and mentored in evolutionary biology.

Project Report

This study accomplished the following significant results: (1) the discovery of major groupings within the family Clavariaceae; (2) discovery of approximately 130 species within the family, half of which are known only from environmental soil studies. This number of species exceeds the number of known species ascribed to the family; (3) the discovery that species that fruit on soil may acquire their nutritive needs from live plants; (4) nine morphological traits are of evolutionary significance; (5) discovery of a new genus with gills or lamellae; (6) production of ca. 500 DNA sequences from four gene regions, including 36 taxonomic type collections; and (7) a systematic revision of species of Clavariaceae from the Pacific Northwest. Results were disseminated at numerous professional and amateur meetings. Two publications ensued, and several others are in various states of preparation. One postgraduate student and one undergraduate student were mentored and trained in aspects of fungal systematics as a result of this project. The study also stimulated an international collaboration with a taxonomist from Slovakia, who visited our research laboratory for two months. Further collaborations were established with citizen scientist, who contributed collections to the project. Several outreach efforts were performed with natural history enthusiasts in California, Arkansas, Tennessee, and North Carolina.

National Science Foundation (NSF)
Division of Environmental Biology (DEB)
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Simon Malcomber
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University of Tennessee Knoxville
United States
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