Titanoboa cerrejonensis was a gigantic snake that lived roughly 60 to 58 million years ago in what's now Colombia — meaning it appeared several million years after the non-avian dinosaurs had already gone extinct, not alongside them.
How big is "titanoboa" big
Based on fossilized vertebrae, Titanoboa is estimated to have reached around 13 meters (42 ft) long and weighed more than 1,000 kg (2,200 lb) — making it the largest snake known to science, well beyond any living species. For comparison, the largest modern snakes, like the green anaconda, top out at roughly 6 to 9 meters.
What its size tells scientists
Snakes are cold-blooded, so their maximum possible size is closely tied to how warm their environment is. Titanoboa's size implies that the tropical regions it lived in shortly after the dinosaurs' extinction were likely warmer than the same regions are today — making Titanoboa fossils a useful clue for reconstructing ancient climate, not just ancient wildlife.
Where it was found
Titanoboa was discovered in the Cerrejón coal mine in Colombia, one of the richest fossil sites for understanding what tropical South America looked like in the first few million years after the dinosaurs disappeared.