Phyllosticta taxa from northern Thailand and southern European Russia: a novel species and four new host records

Abstract

Abstract Phyllosticta is a cosmopolitan group of fungi found on various host plants, occurring as pathogens, endophytes and saprobes. Diseases caused by Phyllosticta commonly include leaf and fruit spots that affect economically important plants. The genus is characterized mainly by aseptate and hyaline conidia and ascospores. However, its conidia are surrounded by a mucilaginous sheath, with a single mucoid apical appendage while ascospores exhibit a mucoid cap at both ends. Given that many Phyllosticta taxa are cryptic and share similar morphological features, it is arduous to depict taxonomically relevant characters solely on the basis of morphological and ecological features. Coupled with morphological description, multi-locus phylogenetic analyses of species comprising complexes are used to broadly describe this genus and understand species boundaries. Despite several published taxonomic revisions and enumerations of Phyllosticta species, there is still considerable confusion when identifying these taxa. Herein, we introduce a new species (P. chiangmaiensis) and three new host records (P. capitalensis) in Thailand, and one new host and country record (P. citribrasiliensis) in Russia. We provide an updated phylogenetic tree, including all Phyllosticta species with sequence data.