(Alex Hastings displays a pelvic bone of Acherontisuchus guajiraensis. Image: Florida Museum of Natural History photo by Kristen Grace)
There's little doubt that Acherontisuchus guajiraensis and Titanoboa competed for food. The former evolved to hunt and eat fish, which the snake also consumed. The genus, Acherontisuchus, is named for the river Acheron from Greek mythology, "the river of woe," since the animal lived in a wide river that emptied into the Caribbean. Its snout was long, narrow and full of pointed teeth, perfect for grabbing lungfish and relatives of bonefish that inhabited the water.
The new species is a dyrosaurid, believed to mostly have been ocean-dwelling, coastal reptiles. The new adult specimens challenge previous theories the animals only would have entered freshwater environments as babies before returning to sea.
During the Paleocene in South America, the environment was dominated by reptiles, including other giant snakes, crocodiles, and turtles. The dyrosaurid family originated in Africa about 75 million years ago, toward the end of the age of dinosaurs, and arrived in South America by swimming across the Atlantic Ocean.