Invertebrates such as spiders and centipedes are underappreciated kings of the jungle, eating a surprising amount of vertebrates in the Amazon, a new study says.

Biologists recently documented 15 interactions in which the invertebrates are hunters and the vertebrates are prey. They captured photo and video evidence of invertebrates eating tadpoles, lizards, snakes—and even an opossum, a first-of-its-kind observation. (Read about tiny spiders that devour lizards three times their size.)

Though such behaviors have been recorded before, the study provides more data about just how many vertebrates fall victim to small predators, particularly spiders.

“Invertebrates preying on vertebrates is common, but it’s generally not assumed to be an important source of mortality for amphibians and reptiles,” says study leader Rudolf von