Philodryas patagoniensis, also known as the Patagonia green racer, is a species of rear-fanged (opisthoglyphous) venomous snake in the family Colubridae.

The species is endemic to cis-Andean South America from northern Argentina to northeastern Brazil; despite its name, most of its range is outside Patagonia.

Females are born with a greater rostro-cloacal length and reach sexual maturity later than males, about 2-years-old.

[4] P. patagoniensis is preyed upon by birds such as Cariama cristata and Tyto alba, as well as other snakes such as Boiruna maculata.

[1] Common names for P. patagoniensis include corre campo, parelheira, parelheira comum, papa pinto, culebra del alfa, culebra de los pastos, ratonera, and mboi hovy.