Reconstructing the Clavariaceae using nuclear large subunit rDNA sequences and a new genus segregated from Clavaria

Abstract

Fungi that produce clavarioid fruit bodies have evolved independently many times in the Basidiomycota. The evolutionary significance of this morphology is difficult to interpret because the phylogenetic positions of many clavarioid fungi are still unknown. In this study we examined the phylogenetic diversity of the Clavariaceae sensu lato among Homobasidiomycetidae by adding partial nuclear large subunit ribosomal DNA sequences from clavarioid and corticioid fungi to a large euagaric dataset and analyzing them both together and separately. Our results indicate that the clavarioid morphology has evolved at least five times in the euagarics while the inclusion of type species enabled us to evaluate the taxonomic consequences of this polyphyletic distribution. Although the sampling available at present is incomplete, a qualitative assessment of our phylogenetic hypotheses indicates that the clavarioid habit might not be as evolutionary labile as previously reported. We propose the new genus Alloclavaria to accommodate Clavaria purpurea, which is not related to Clavaria but is derived within the hymenochaetoid clade. The Physalacriaceae and Clavariaceae are redefined to reflect monophyletic groups, and the limits of Clavaria, Clavulinopsis and Ramariopsis should be reconsidered when additional data are available.

• Actiniceps
• agaric
• Chaetotyphula
• clamp connection
• coral mushroom
• Dimorphocystis
• Eumycota
• Holocoryne
• Hymenomycetes
• Macrotyphula
• molecular systematics
• morphological evolution
• Physalacria
• Typhula

The authors express their gratitude to everyone who has helped with this research, including: Luis Diego Gomez, Las Cruces Biological Station (Organization for Tropical Studies, San Vito, Costa Rica); Julieta Carranza, Univ. of Costa Rica, Nancy Aitkin, Priscilla Zamora, and the staff at Proyecto Campanario (Osa Peninsula, Costa Rica), Zana Finkenbinder and the Quetzal Education and Research Center (San Gerardo de Dota, Costa Rica); Benito Tan and Teck Koon Tan, National Univ. of Singapore, and Ruth Kiew and the Garden staff at the Singapore Botanic Gardens and Herbarium; D.M. Geiser and J.W. Taylor, Univ. of California at Berkeley; Jean Lodge, USDA (Puerto Rico); Peter Buchanan, Univ. of Auckland and the LandCare Research Herbarium (New Zealand); Meredith Blackwell, Louisiana State Univ. (Baton Rouge); Esther McLaughlin and Rachel Mason Dentinger for invaluable advice, expertise and field assistance; Keith Barker, Sharon Jansa and the Zink Lab for help with sequencing and editing of the massive data matrix. We thank Robert Sonkowsky for help with the Latin translation. This research was supported by John W. Hall Memorial Research Fund (Univ. of Minnesota), a Bush Sabbatical Fellowship (Univ. of Minnesota), and in part by NSF DEB-9306578 and NSF EF-0228671 to DJM.