Differentiation of species complexes in Phyllosticta enables better species resolution

Abstract

Phyllosticta species have worldwide distribution and are pathogens, endophytes, and saprobes. Taxa have also been isolated from leaf spots and black spots of fruits. Taxonomic identification of Phyllosticta species is challenging due to overlapping morphological traits and host associations. Herein, we have assembled a comprehensive dataset and reconstructed a phylogenetic tree. We introduce six species complexes of Phyllosticta to aid the future resolution of species. We also introduce a new species, Phyllosticta rhizophorae isolated from spotted leaves of Rhizophora stylosa in mangrove forests of Taiwan. Phylogenetic analysis based on combined sequence data of ITS, LSU, ef1α, actin and gapdh loci coupled with morphological evidence support the establishment of the new species. We synonymize strains of P. capitalensis (CPC 20508 and CPC20509) under the new species. Six strains (CBS 173.77, CBS 119720, CPC 17748, CPC 20252, CPC 20269, and CBS 123404) are unnamed species based on phylogenetic analyses and nucleotide polymorphisms and probably represent new species. The phylogenetic relationships of Phyllosticta species are reappraised and suggestions are given for future work.