Amphisbaena mertensii is a worm lizard species from South America. Because of its subterranean lifestyle,data on its biology are scarce. In this paper, we present the first record of A. mertensii as prey of a bird, the wood rail Aramides cajaneus. We also review the geographic range of this species, reporting it for 114 localities from west-central Brazil to northeastern Argentina. We update the range of precloacal pores in A. mertensii from 5–8 to 4–8, and report the largest individual of this species with a 458 mm snout-vent length.