All extant amphisbaenians – the weird, burrowing squamates often vernacularly termed worm-lizards – are predators that prey on arthropods, worms and small vertebrates. They catch animals in tunnels, often immobilising prey by holding them against a tunnel wall with a curve of the body.
Some amphisbaenians – among them the large South American Amphisbaena species – take surprisingly large prey and regularly kill other reptiles as well as rodents. When hunting such surface-dwelling prey, the amphisbaenian lunges forward with its mouth open, grasping the prey with a powerful bite and dragging it underground or tearing a chunk from its body, sometimes by powerfully twisting as it withdraws. Amphisbaenians return to disabled or deceased prey and it has been suggested that they may scavenge from dead bodies lying on the surface.
And herein we find the inspiration for the giant Graboidus and small land-candirus of the Squamozoic.
Amphisbaenians have been mentioned a few times on Tet Zoo before. See...
Darren Naish is a science writer, technical editor and palaeozoologist (affiliated with the University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs but has an avid interest in all things tetrapod. His publications can be downloaded at darrennaish.wordpress.com. He has been blogging at Tetrapod Zoology since 2006. Check out the Tet Zoo podcast at tetzoo.com! Follow Darren Naish on Twitter