This bird, sometimes called the Giant Teratorn, is an extinct species known (as of 2006) from three sites from the late Miocene (6 million years before present) of central and northwestern Argentina, where a good sample of fossils has been obtained. The humerus (upper arm bone) of Argentavis is somewhat damaged.

What made Argentavis go extinct?

Argentavis was a member of an extinct group of predatory birds understandably called the teratorns – 'monster birds'. They are related to storks and New World vultures such as turkey vultures and condors. ... He found that Argentavis simply couldn't have generated enough lift from a running-take-off.

When did Argentavis exist?

The Giant Teratorn — Argentavis magnificens — was an absolutely enormous species of flying bird which lived in Argentina during the late Miocene, about six million years ago.