|BONITO, GREGORY - Michigan State University|
|CROUS, PEDRO - Biodiversity Research Center, Academia Sinica (BRCAS)|
|HEALY, ROSANNE - Harvard University|
|KOVACS, GABOR - Eotvos Lorand University|
|LOBUGLIO, KATHERINE - Harvard University|
|O Donnell, Kerry|
|PFISTER, DONALD - Harvard University|
|SMITH, MATTHEW - University Of Florida|
|TRAPPE, JAMES - Oregon State University|
|ZHUANG, WEN-YING - Chinese Academy Of Sciences|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/23/2015
Publication Date: 4/23/2015
Citation: Bonito, G., Crous, P.W., Healy, R.A., Kovacs, G.M., Lobuglio, K., O'Donnell, K., Pfister, D.H., Smith, M.E., Trappe, J.M., Zhuang, W. 2015. Phylogenetic assessment of Pezizomycetes [abstract].
Technical Abstract: Pezizomycetes and Orbiliomycetes form the earliest diverging lineage within the Pezizomycotina. A shared derived character, the operculate ascus, supports Pezizomycetes monophyly, although functional opercula have been lost in certain taxa (mostly truffles and truffle-like forms). This class contains c. 1700 described species, classified in 200 genera and 15 families within the Pezizales. It is highly diverse both morphologically and ecologically. Until recently, most Pezizomycetes that produce apothecia epigeously were thought to be primarily saprobic and rarely plant pathogenic, but an increasing number of species are being identified as ectomycorrhizal/symbiotic using molecular techniques. Furthermore, several groups have been found as orchid associates, foliar endophytes or endolichenic. These species occur in a broad range of habitats and many are substrate specialists, producing apothecia on all types of soil, including burnt ground, on dung, decaying leaves, needles, wood, and living mosses. Previous class-wide phylogenetic analyses of rDNA sequences suggested 3 or 5 distinct clades within the Pezizomycetes: A) Ascobolaceae and Pezizaceae; B) Discinaceae-Morchellaceae and Helvellaceae-Tuberaceae; and C) Ascodesmidaceae, Chorioactidaceae, Glaziellaceae, Pyronemataceae, Sarcoscyphaceae, and Sarcosomataceae. The Caloscyphaceae-Karstenellaceae and Rhizinaceae were either resolved in clade B or as two independent lineages. None of these clades/lineages correspond to earlier proposed suborders. Clades A and B are supported by certain morphological features, e.g. ascus reaction in iodine, cytology of spores and paraphyses, septal pore ultrastructure, and excipulum structure, although these characters exhibit some homoplasy. Lineage C is the largest and most heterogeneous group; no unifying morphological features support its recognition. However, based on phylogenetic analyses that included portions of three protein-coding genes (RPB1, RPB2 and TEF1), the Chorioactidaceae, Sarcoscyphaceae, and Sarcosomataceae formed a monophyletic group that corresponds to the previously recognized suborder Sarcoscyphineae. The latter was resolved as a sister group to the rest of clade C. Interestingly, these analyses also suggested the plant parasitic Caloscyphaceae-Rhizinaceae represented a monophyletic group that was sister to clade B. During the past 10-15 years, two families were newly described while others were re-circumscribed or re-erected. Several open questions remain including: 1) placement of several genera that phylogenetic results suggest should be removed from the Pyronemataceae, 2) family assignment of the ‘gymnohydnotrya clade’, and 3) phylogenetic placement of several enigmatic species/genera (e.g., Strobiloscypha). Several genera have been shown to be polyphyletic and additional sampling of species are needed to re-circumscribe these; other genera still need to be targeted for molecular phylogenetics. In this joint community paper, we aim to robustly resolve the deeper branches in the Pezizomycetes phylogeny to propose pertinent orders for an updated classification that more accurately reflects evolutionary relationships. In addition, research will focus on resolving family limits and placement of genera. Although a large number of sequences are available from the nuclear LSU rDNA, RPB1, RPB2 and TEF1 from various family and generic studies, future research is needed to sample missing genes and taxa to resolve evolutionary relationships of all of the families and lineages.