Three new species of Pewenomyces (Coryneliaceae) from Araucaria araucana in Chile

Abstract

The Coryneliaceae is a relatively small family of mainly pathogenic fungi occurring on a diversity of hosts with a wide global distribution. Members of the family are recognized by their black, upright and elongated ascomata. Historically, the taxonomy of this group was mainly based on morphological characters, but in more recent years, DNA sequence data have resulted in new revisions. The genus Pewenomyces was recently described based on P. kutranfy, a canker pathogen on Araucaria araucana in Chile. Morphologically, this fungus resembles species in Caliciopsis and Hypsotheca. During the study in which Pewenomyces was described, three putative species were identified from the same host, two of which were observed only from cultures obtained by isolating from plant tissues. At the time of describing P. kutranfy, there was uncertainty regarding its novelty because two species of Caliciopsis (C. brevipes and C. cochlearis), a closely related genus in the Coryneliaceae, had previously also been described from the same host and location, but for which DNA sequence data were not available. In this study, phylogenetic analyses that were carried out for the three putative Pewenomyces species using sequences for seven gene regions confirmed that they were distinct species. Herbarium specimens for the two Caliciopsis species were obtained for morphological comparisons and phylogenetic analyses. Although the holotypes for the two Caliciopsis species did not yield adequate DNA for a phylogenetic analysis, a detailed morphological study established that these species were clearly different from any of the Pewenomyces taxa. The three putative species are consequently described here as Pewenomyces lalenivora sp. nov., P. tapulicola sp. nov., and P. kalosus sp. nov.