Galinsoga parviflora is an herbaceous dicotyledonous plant in the Asteraceae that is common in disturbed habitats and agricultural areas across various temperate and subtropical regions of the world. In this study, several pathogenic strains were isolated from this host, and further morphological and phylogenetic analysis of DNA sequences of nuclear rDNA ITS1-5.8S-ITS2 (ITS barcode) and five other gene regions (act, chs-1, gapdh, his3, and tub2) revealed a new species, described here as Colletotrichum galinsogae sp. nov. The pathogenicity of C. galinsogae sp. nov. was also tested and confirmed on leaf segments and seedlings of G. parviflora.
