Three species of Ideopsis are known from Thailand: Ideopsis vulgaris, Ideopsis similis and Ideopsis gaura.
Ideopsis vulgaris and Ideopsis similis look very similar and they can also be easily confused with Parantica agleoides and Parantica aglea.
The shape and arrangement of the markings on the wings between the Ideopsis species and Parantica species are a little different.
The shape of certain white spots on the underside of the wings determines whether it is Ideopsis vulgaris or Ideopsis similis.

Khao Sok National Park, Surat Thani Province, Thailand, 23 & 24 January 2013