Ideopsis is a genus of nymphalid butterflies in the subfamily Danainae found in South-east Asia.

Large, slender, black and light blue or white butterflies. The body appears strikingly small and thin compared to the large wings. The genus resembles the genus of wood nymphs ( Idea spp.), but these butterflies are smaller than the wood nymphs.The clubbed antennae and particularly the genitalia distinguish it from Hestia, as also its generally very striking sexual dimorphism

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