Researchers have made a remarkable discovery in Burmese amber, unveiling a 100-million-year-old firefly fossil that sheds light on the early evolution of insect bioluminescence. This finding provides a fascinating glimpse into the past, shedding new insights on the origins and development of this captivating natural phenomenon.
Illuminating the Past
For centuries, bioluminescence—the species-specific ability of living organisms to produce light—has intrigued both scientists and poetics in the natural world. Fireflies specifically, are a group of insects which have fascinated people all around the globe with their entrancing displays of light.
A team of scientists, headed by Professor CAI Chenyang from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS), recently discovered four new species with complete front and hind wings in Burmese amber. Previously, they uncovered the exquisitely preserved fossil of a female firefly from the mid-Cretaceous, about 100 million years ago. The finding is only the second firefly fossil ever discovered from the Mesozoic, and it offers a rare glimpse into how ancient bioluminescent insects might have had to evolve in early ecological relationships with encroaching angiosperms.
The Cretaceous fireflies mystery unlocked
Named Flammarionella hehaikuni Cai, Ballantyne, & Kundrata, 2024 has the oldest fossil-ranked split in one of the basal lineages of lucioline fireflies (Lampyridae). The species displays a number of intriguing characteristics which provide clues to how bioluminscence may have evolved early on.
One of the most interesting features in the fossil is oval sensory receptors on its astennae, segmented from 3 to 11. The existence of these specialized olfactory organs indicates that the ancient firefly would have had an advanced sense of smell — a feature likely linked to the species’ ability to survive and reproduce.
Furthermore, the light-emitting organ at the base of the metasoma appears indistinguishable from that of a modern Luciolinae firefly and suggests an extraordinary degree of evolutionary stasis for this trait. In combination with other findings of bioluminescent beetles from the Cretaceous, this specimen from Myanmar suggests that an outstanding diversity of light organs in rove beetles had already evolved in the Mesozoic.
Conclusion
Here we report the discovery of a mid-Cretaceous Burmese amber inclusion that documents the earliest crown-group gunpowder explosiveness in an adult firefly (Coleoptera: Lampyridae). This discovery not only provides a special view into the past, but also highlights why it is so important for us to keep on fossil hunting to put life’s puzzle together. As we test and investigate these ancient pieces, surely there will be yet more insights to come from the history and evolution of this amazing biological feature.
