Laophis (From Ancient Greek, stone snake) is a genus of viperid snake currently containing one known species that lived during the Pliocene in Northern Greece. Few fossil vertebrae of this species was found in Thessaloniki, Greece. It reached a total length possibly exceeding and a mass of up to , making this perhaps the largest viper discovered yet. Originally described by Sir Richard Owen, the original fossils had been lost, until a single vertebra was discovered somewhere near Thessaloniki in 2014.