Multigene phylogeny of the Coronophorales: morphology and new species in the order

Mycologia. 2010 Jan-Feb;102(1):185-210. doi: 10.3852/09-043.

Abstract

The phylogenetic relationships within Coronophorales have been debated because of uncertainty over the taxonomic usefulness of characteristics such as quellkörper, number of ascospores per ascus, presence of ascospore appendages, presence of subiculum and ascomatal vestiture. The phylogenetic relationships are examined with DNA sequence data from three nuclear genes targeting 69 taxa and 130 new sequences representing collections from Africa and the Americas. Analyses recovered monophyletic Bertiaceae, Chaetosphaerellaceae and Scortechiniaceae and a paraphyletic Nitschkiaceae. A single collection of Coronophora gregaria is included and Coronophoraceae is accepted. Bertiaceae is expanded to include Gaillardiella, and Thaxteria is synonymized with Bertia with a new combination, B. didyma. Three new species of Bertia are described: B. ngongensis from Kenya, B. orbis from Kenya and Costa Rica and B. triseptata from Ecuador and Puerto Rico. Bertia gigantospora is transferred from Nitschkia. Scortechiniaceae is confirmed for the quellkörper-bearing taxa including monotypic Biciliospora, Coronophorella, Neofracchiaea, Scortechiniella and Scortechiniellopsis. Tympanopsis is reinstated for T. confertula and T. uniseriata, while Scortechinia is more narrowly circumscribed to include S. acanthostroma and the new species, S. diminuspora from Ecuador. Cryptosphaerella is accepted in Scortechiniaceae including six new species from Kenya and Costa Rica, C. celata, C. costaricensis, C. cylindriformis, C. elliptica, C. globosa and C. malindensis. Spinulosphaeria is accepted in Coronophorales with uncertain family placement. The number of ascospores in the ascus is not phylogenetically useful in distinguishing genera within the order. The quellkörper continues to be an important character in defining the Scortechiniaceae, while taxa within the group show a mixture of morphological characteristics of varying phylogenetic importance. The presence of smooth versus spinulose subiculum aids in separating Tympanopsis and Scortechinia, and erumpent ascomata distinguish Cryptosphaerella species. Taxa within the Bertiaceae vary along the lines of robust, tuberculate, collapsing ascomata and large, hyaline to pigmented, septate ascospores.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Ascomycota / classification*
  • Ascomycota / genetics
  • Ascomycota / ultrastructure
  • DNA, Fungal / analysis
  • DNA, Fungal / genetics
  • DNA, Ribosomal / analysis
  • DNA, Ribosomal / genetics*
  • DNA-Directed RNA Polymerases
  • Genes, Fungal*
  • Kenya
  • Peptide Elongation Factor 1 / genetics*
  • Phylogeny*
  • RNA Polymerase II / genetics*
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Species Specificity
  • Spores, Fungal / ultrastructure

Substances

  • DNA, Fungal
  • DNA, Ribosomal
  • Peptide Elongation Factor 1
  • RNA Polymerase II
  • DNA-Directed RNA Polymerases
  • RNA polymerase beta subunit