Colletotrichum fioriniae infecting invasive Japanese hop (Humulus scandens) in the United States.

Japanese hop (Humulus scandens) is a non-native, invasive plant that colonizes disturbed riparian areas throughout the eastern United States and Canada, forming dense, monocultural stands that displace native plant communities due to a high reproductive rate, rapid growth, climbing bines, and dense shading (Balogh and Dancza 2008). It is capable of serving as a reservoir for agronomically important plant pathogens, such as the Tomato spotted wilt virus and powdery mildew species that infect commercial hemp and hop fields (Yoon et al. 2018; Weldon et al.

, sp. nov., a newly described rust on the federally endangered plant, California sea-blite ().

Rust disease was observed on populations of near Morro Bay, California. The pathogen was identified as a species of based on teliospore and urediniospore morphology and nuc 28S rDNA sequence analysis. The isolate was compared with previously described species of that infect members of Chenopodiaceae, prompting a taxonomic reevaluation of species on .