Phylogenetic and taxonomic evaluation of Chalara, Chalaropsis, and Thielaviopsis anamorphs associated with Ceratocystis

Parsimony analysis of sequences of the in- ternal transcribed spacer region of the nuclear rDNA and partial sequences of the large subunit (LSU) place four anamorphic Chalara species as a monophy- letic grouping within the teleomorph genus Ceratocys- tis. Chalara ovoidea, Ch. thielavioides, Ch. populi, and Ch. elegans (synanamorph: Thielaviopsis basicola) form aleurioconidia typical of the anamorph genus Thiela- viopsis, to which the species are transferred. Three of these species (T. ovoidea, T. thielavioides, and T. populi) are morphologically similar to each other but are shown to be distinct by rDNA sequences. The ana- morphic genera Chalaropsis and Hughesiella are con- sidered synonyms of Thielaviopsis. Thielaviopsis punc- tulata, which forms aleurioconidia singly, is shown to be the anamorph of Ce. radicicola. The respective an- amorphs for Ce. coerulescens, Ce. fagacearum, and Ce. eucalypti, which lack aleurioconidia, are also trans- ferred to the amended genus Thielaviopsis as T. un- geri, T. quercina, and T. eucalypti. Although Ch. aus- tralis and Ch. neocaledoniae do not form aleurioconi- dia, they are placed in Thielaviopsis based on their endoconidial state and clear affinities to Ceratocystis eucalypti. Three apparently asexual Ambrosiella species belong in the Ce. moniliformis clade based on LSU rDNA sequences, but the cultures available are not suitable for detailed morphological study, and these