Molecular phylogenetics of the gomphoid-phalloid fungi with an establishment of the new subclass Phallomycetidae and two new orders

Abstract

Molecular phylogenetic analyses for the gomphoid-phalloid fungi were conducted based on the five gene dataset with extensive taxon sampling. The monophyly of the gomphoid-phalloid clade was strongly supported, and four well supported major subclades were recognized. Three of the four sub-clades were represented entirely by gastroid taxa, and only Gomphales contained both gastroid and non-gastroid taxa. While the gastroid morphology is derived from epigeous, nongastroid taxa in Gomphales, the topology of Phallales indicated that truffle-like form is an ancestral morphology of the stinkhorn fruiting bodies. Although basidiospore maturation occurs within the enclosed fruiting bodies of the stinkhorn, the elevation of the mature spore-producing tissue represents an independent origin of the stipe among Basidiomycota. Comparisons are made between previous and new classification schemes, which are based on the results of phylogenetic analyses. Based on the results of these analyses, a new subclass Phallomycetidae, and two new orders, Hysterangiales and Geastrales, are proposed.

• atp6
• EF-1α
• homobasidiomycetes
• rDNA
• RPB2
• systematics

We thank these individuals for providing specimens: Youko Andoh, Manfred Binder, Lisa Grubisha, Steve Miller, Jean-Marc Moncalvo, Tetsuo Muroi, Hiromi Sasaki, Akiyoshi Yamada and Kazumasa Yokoyama. We acknowledge Ikuo Asai, Efren Cazares, Peter Johnston, Patrick Leacock and Koukichi Maruyama for providing color photos. We also acknowledge Drs Hanns Kreisel, David Hawksworth, Vincent Demoulin and Shaun Pennycook for providing the nomenclatural history of Geastrales and Phallales. Thanks also go to Dr Reinhard Agerer for providing the information on rhizomorphic structures and Dr Susie Dunham for identifying the hyphal mats. This research project was financed in part by the National Science Foundation, Doctoral Dissertation Improvement Grant (DEB-0309412) to KH. We also acknowledge support from NSF 0090301, Research Coordination Network: a phylogeny for kingdom Fungi to M. Blackwell, J.W. Spatafora, and J.W. Taylor.