Multigene phylogenetic analyses of the Thelonectria coronata and T. veuillotiana species complexes

作者：Salgado Salazar Catalina^*; Rossman Amy; Samuels Gary J; Capdet Mariana; Chaverri Priscila

来源：Mycologia, 2012, 104(6): 1325-1350.

DOI：10.3852/12-055

• Ascomycota
• fungi
• homothallic
• Hypocreales
• Neonectria
• phylogenetic analyses
• species concept
• taxonomy

Thelonectria is a recently established genus of common and ubiquitous fungi on woody hosts, previously placed in the genus Neonectria. Thelonectria coronata and T. veuillotiana occur sympatrically in tropical, subtropical and temperate regions. Previous taxonomic studies including T. coronata and T veuillotiana suggested these fungi could represent species complexes; however, the morphological features used to define species exhibited few differences useful for testing this hypothesis. To assess the status of T. coronata and T. veuillotiana, phylogenetic analyses of six genomic regions were combined with a morphological examination of specimens. A multigene phylogeny reconstructed with maximum parsimony, maximum likelihood and Bayesian approaches identified five phylogenetic groups in T. coronata and six in T. veuillotiana. As is common for cryptic species, unequivocal diagnostic morphological characters could not be identified; however, average values of morphological traits correspond to the phylogenetic groups. An increased number of non-synonymous/synonymous substitutions in the beta-tubulin gene and a decreased or absent production of conidia were detected within the T coronata complex, possibly indicating the homothallic nature of these isolates. T. caronata and T. veuillotiana and related species are described and illustrated here; a dichotomous key to all species is provided.

• 出版日期2012-12