PREY ATTRACTION AS A POSSIBLE FUNCTION OF BIOLUMINESCENCE IN THE LARVAE OF PYREARINUS TERMITILLUMINANS (COLEOPTERA: ELATERIDAE)

Elaterid beetle larvae. Pyrearinus termitilluminans (sp.n., Costa, 1982.) live in termite mounds in central Brazil. Each larva produces light in the segment immediately behind its head. Larvae were observed to luminesce only during the first weeks of the rainy season, the same times as the ant and termite alate flights. Alates, apparently attracted to P. termitilluminans larval lights, serve as an important food source for the larvae. The prey-catching and food-storing behavior and the phenomenon of bioluminescence are appa-rently an evolutionary response by P. termitilluminans larvae to a short, rich pulse of food. Prey attraction as a probable cause for luminescence has been suggested only twice before. Over twenty functions of bioluminescence have been advanced (Buck, 1978). Prey attraction has been suggested as a probable cause for luminescence in only two cases, benthic fishes (refs. in Buck, 1978) and fungus gnats (refs. in Lloyd, 1978; Sivinski, in press). This study reports an additional example of prey attraction in a Neotropical elaterid beetle larva, pyrearinus termitil-luminans. As early as 1850 travelers to central Brazil have reported termite mounds with "pale glows of phosphorescent light, like coals in the ashes " (Smith, 1879; Castelnau in Branner, 1909). Various explanations were offered for these mysterious lights, from fungus and bacteria to the termite mounds themselve