Key: Collin, J. E. (1944). The British species of Psilidae (Diptera). Entomologist’s Monthly Magazine, 81, 214–224.
Europe: Countries (published), online at Fauna Europaea, Occurrences at GBIF
UK: Recording Scheme map of occurrences 2016 (verified.) Online (NBN Atlas) via Easy maps or Interactive Atlas - all mixed in with Ch. unilineata