The differences are slight in the male genitalia between hostilis and adelphella. The valva shape differs with the thickening in adelphella being more curved. The juxta are different shapes. The uncus is wider/more parallell sided in adelphella. The thickening in the duct of the aedeagus is more developed in adelphella. The part of the aedeagus with many small spines is well developed in hostilis.
Administered by the Lepidoptera Dissection Group UK. This website presents images of British and European Lepidoptera preparations.
It is designed as a reference tool to augment information provided in literature.