Source: False Eyes of a Hawkmoth Caterpillar by melvynyeo on DeviantArt

The author says:

False Eyes of a Hawkmoth Caterpillar (Green pergesa hawkmoth, Pergesa acteus). When at rest, its false eye wasn’t visible as seen in the pic… when disturbed, it will tucked in its head and expose the false eye! Pretty cool! :) Taken at night in Singapore forest.

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