- the wingless female or larva of the European beetle, Lampyris noctiluca, which emits a sustained greenish light.
- any of various other beetle larvae or wingless females that emit a glow rather than a flash of light.
- a European beetle, Lampyris noctiluca, the females and larvae of which bear luminescent organs producing a greenish light: family Lampyridae
- any of various other beetles or larvae of the family Lampyridae
