Lagena—an overlooked oomycete genus with a wide range of hosts

Abstract Lagena has so far only been known from the scarcely reported but widespread species radicicola , which is a parasite of root epidermal cells. While it was mostly wide range cereals and other grasses, shown to affect some dicot under, e.g. tobacco sugar beet. Due host spectrum under laboratory conditions, there were no attempts subdivide genus into several species, even though morphological differentiation had found in continents. During survey diatoms, we came across parasitoids that would have previously assumed be members Lagenidium . The exhibited rather narrow specificity nature. One brought dual culture with diatoms Ulnaria could not transferred genera. Surprisingly, phylogenetic analyses revealed sister clade formed by diatom parasitoids, suggesting versatile pathogenicity genus. Interestingly, lineages environmental sequencing clustered this study, hinting an undiscovered diversity