The Ascomycota tree of life: a phylum-wide phylogeny clarifies the origin and evolution of fundamental reproductive and ecological traits.
We present a 6-gene, 420-species maximum-likelihood phylogeny of Ascomycota, the largest phylum of Fungi. This analysis is the most taxonomically complete to date with species sampled from all 15 currently circumscribed classes. A number of superclass-level nodes that have previously evaded resolution and were unnamed in classifications of the Fungi are resolved for the first time. Based on the 6-gene phylogeny we conducted a phylogenetic informativeness analysis of all 6 genes and a series of ancestral character state reconstructions that focused on morphology of sporocarps, ascus dehiscence, and evolution of nutritional modes and ecologies. A gene-by-gene assessment of phylogenetic informativeness yielded higher levels of informativeness for protein genes (RPB1, RPB2, and TEF1) as compared with the ribosomal genes, which have been the standard bearer in fungal systematics. Our reconstruction of sporocarp characters is consistent with 2 origins for multicellular sexual reproductive structures in Ascomycota, once in the common ancestor of Pezizomycotina and once in the common ancestor of Neolectomycetes. This first report of dual origins of ascomycete sporocarps highlights the complicated nature of assessing homology of morphological traits across Fungi. Furthermore, ancestral reconstruction supports an open sporocarp with an exposed hymenium (apothecium) as the primitive morphology for Pezizomycotina with multiple derivations of the partially (perithecia) or completely enclosed (cleistothecia) sporocarps. Ascus dehiscence is most informative at the class level within Pezizomycotina with most superclass nodes reconstructed equivocally. Character-state reconstructions support a terrestrial, saprobic ecology as ancestral. In contrast to previous studies, these analyses support multiple origins of lichenization events with the loss of lichenization as less frequent and limited to terminal, closely related species.
Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA.
Conrad L
CL
Schoch
Gi-Ho
GH
Sung
Francesc
F
López-Giráldez
Jeffrey P
JP
Townsend
Jolanta
J
Miadlikowska
Valérie
V
Hofstetter
Barbara
B
Robbertse
P Brandon
PB
Matheny
Frank
F
Kauff
Zheng
Z
Wang
Cécile
C
Gueidan
Rachael M
RM
Andrie
Kristin
K
Trippe
Linda M
LM
Ciufetti
Anja
A
Wynns
Emily
E
Fraker
Brendan P
BP
Hodkinson
Gregory
G
Bonito
Johannes Z
JZ
Groenewald
Mahdi
M
Arzanlou
G Sybren
GS
de Hoog
Pedro W
PW
Crous
David
D
Hewitt
Donald H
DH
Pfister
Kristin
K
Peterson
Marieka
M
Gryzenhout
Michael J
MJ
Wingfield
André
A
Aptroot
Sung-Oui
SO
Suh
Meredith
M
Blackwell
David M
DM
Hillis
Gareth W
GW
Griffith
Lisa A
LA
Castlebury
Amy Y
AY
Rossman
H Thorsten
HT
Lumbsch
Robert
R
Lücking
Burkhard
B
Büdel
Alexandra
A
Rauhut
Paul
P
Diederich
Damien
D
Ertz
David M
DM
Geiser
Kentaro
K
Hosaka
Patrik
P
Inderbitzin
Jan
J
Kohlmeyer
Brigitte
B
Volkmann-Kohlmeyer
Lizel
L
Mostert
Kerry
K
O'Donnell
Harrie
H
Sipman
Jack D
JD
Rogers
Robert A
RA
Shoemaker
Junta
J
Sugiyama
Richard C
RC
Summerbell
Wendy
W
Untereiner
Peter R
PR
Johnston
Soili
S
Stenroos
Alga
A
Zuccaro
Paul S
PS
Dyer
Peter D
PD
Crittenden
Mariette S
MS
Cole
Karen
K
Hansen
James M
JM
Trappe
Rebecca
R
Yahr
François
F
Lutzoni
Joseph W
JW
Spatafora
D001203:Ascomycota / Q000145:classification / Q000166:cytology / Q000235:genetics*; D017753:Ecosystem; D005800:Genes, Fungal; D010802:Phylogeny; D012098:Reproduction