Three novel species of Asterina (Asterinales, Dothideomycetes) from Hainan Province, China

Asterina comprises obligate biotrophic fungal pathogens that form black colonies on the surface of living leaves and derive nutrients by penetrating host epidermal cells, often resulting in tissue damage. In this study, three new species of Asterina from Hainan Province, China, are described based on morphological characteristics and multi-gene phylogenetic analyses (nrITS, nrLSU, and nrSSU), with phylogenetic relationships inferred by maximum likelihood (ML) and Bayesian inference (BI) to resolve their taxonomic placement.

The new species Asterina breyniicola, A. heyneicola, and A. olaciphila were collected from living leaves of Breynia fruticosa, Heynea trijuga, and Olax scandens. Detailed morphological descriptions, illustrations, and a phylogenetic tree illustrating their positions are provided. These findings expand the known diversity of Asterina and provide integrated morphological and molecular evidence to improve species delimitation and classification within Asterinaceae.