The monotypic Knudsonia new genus is described for Knudsonia lathraeata new species. The new species and genus are placed in the larentiine tribe Dyspteridini Hulst and hypothesized to be closely related to Celonoptera Lederer and Heterophleps Herrich-Schäffer. Adult morphology, including male and female genitalia are illustrated, and molecular data that supports the new genus are reviewed.