Deep beneath the Amazon rain forest lives a cave-climbing fish—and scientists have captured it on film for the first time.

A team exploring limestone caves near Tena, Ecuador (map), found the gravity-defying fish scaling near-vertical rock walls some 10 feet (3 meters) above an underground stream.

They later identified the species as Chaetostoma microps, a member of the suckermouth armoured catfish family (Loricariidae), according a study published April 16 in the journal Subterranean Biology.