Brazilian species of luminescent Elateridae: luciferin identification and bioluminescence spectra

Abstract In vivo and in vitro bioluminescence spectral data are presented for 12 species of Elateridae (two tribes, four genera) in distinct stages of their life cycle. In adults, the emission color from the abdominal light organ is always shifted (20–40 nm) towards the red relative to that from the prothoracic lanterns (525–560 nm). Thin layer chromatography in five different elution conditions revealed that the luciferin extracted from 13 elaterid species, at different stages of development and from either the thoracic or abdominal lanterns, is the same as that of firefly luciferin. The spectral data suggest the occurrence of luciferase isozymes in the abdominal and thoracic lanterns and in the four metamorphic stages. The bioluminescence intensity from Pyrearinus termitilluminans eggs and larvae increases sharply upon increasing the temperature, with an apparent activation energy of ca 25 kcal mol −1 ( in vitro E a ∼ 16 kcal mol −1 . Field and laboratory observations show that light emission by elaterid larvae serves hunting and defense purposes.