Ancient Gecko Preserved in Amber Reveals Male Anatomy

Paleontologists in Myanmar discovered a 99-million-year-old gecko preserved in amber, identifying it as the oldest known male of its kind. Named Carinasquama rusmithii, the gecko lived during the mid-Cretaceous period in tropical forests.

The remarkably preserved specimen exhibits a swelling at the base of its tail, indicating the presence of hemipenes, paired copulatory organs common in male lizards and snakes. This discovery is unusual because soft tissue structures rarely fossilize, especially in rock formations.

Researchers used micro-CT scanning to reconstruct the gecko’s skeleton and examine the surrounding skin and scales in detail. While the gecko’s exact place on the gecko family tree is still debated, scientists believe it belongs to the Pan-Gekkota group. The finding offers a rare glimpse into the reproductive anatomy of ancient squamates and provides a new method for determining sex in fossilized remains beyond skeletal features.