Gelatine Slug Caterpillar (Cup Moth, Limacodidae)

Larvae might be confused with the similarly flattened larvae of lycaenid butterflies, but those caterpillars have prolegs, are always longer than they are wide, and are always densely covered in short or long setae (hair-like bristles). The head is extended during feeding in the lycaenids, but remains covered in the Limacodidae.