Paleontologists have discovered a fossilized male firefly with large eyes and slender, thread-like antennae preserved in Burmese amber from Myanmar. Research has shown that this is the oldest known firefly, dating back nearly 100 million years to the age of the dinosaurs.

The new species has been named Cretoluciola birmana, reflecting its origin from the Cretaceous period (approximately 98–99 million years ago). To determine its place in evolutionary history, scientists conducted a comparative analysis of more than 400 morphological traits and genetic sequences of modern fireflies.

Based on the collected data, a phylogenetic tree was constructed, confirming with 99.7% probability that the specimen belongs to the Luciolinae family from the Cretaceous period. This indicates that the lineage of modern representatives of this family stretches back almost 100 million years.

The fossil represents a male measuring 6.6 millimeters in length, with large, protruding eyes and thin antennae. Its excellent state of preservation allowed researchers to observe six abdominal segments and a bilateral light-producing organ, similar to those found in modern fireflies.

This discovery suggests that the characteristic bioluminescent glow and flashing system (“on–off”) of fireflies have remained unchanged for tens of millions of years. It is believed that, like their modern counterparts, ancient fireflies used their light to attract mates and send warning signals.

The discovered specimen is the only known representative of its species. To gain a fuller understanding of firefly history, it is necessary to study more ancient insects preserved in amber and to collect a broader sample of modern fireflies.