[3] Before the Paleocene constrictor genus Titanoboa was described from Colombia in 2009, Gigantophis garstini was regarded as the largest snake ever recorded.

It lived about 40 million years ago during the Eocene epoch of the Paleogene Period, in the Paratethys Sea, within the northern Sahara, where Egypt[4] and Algeria are now located.

Jason Head, of the Smithsonian Institution in Washington, DC, has compared fossil Gigantophis garstini vertebrae to those of the largest modern snakes, and concluded that the extinct snake could grow from 9.3 to 10.7 m (30.5 to 35.1 ft) in length.

[5][6] Later estimates, based on allometric equations scaled from the articular processes of tail vertebrae referred to Gigantophis garstini, revised the length of Gigantophis garstini to 6.9 ± 0.3 metres (22.64 ± 0.98 ft).

Its discovery was published in 1901 by paleontologist Charles William Andrews, who described it, estimated its length to be about 30 feet, and named it garstini in honor of Sir William Garstin, KCMG, the Under Secretary of State for Public Works in Egypt.