Bibliotheca Herpetologica 20(5)

Ineich, I., N. Robin, and M. O’Shea. 2026. Was the world’s largest snake measured by a French missionary? A critical analysis of a giant Simalia amethistina (Schneider, 1801) reported in Papua New Guinea. Bibliotheca Herpetologica 20(5):53–60.

The literature is replete with references to giant snakes of modern (non-fossil) origin, but critical analysis generally leads to questioning the sizes reported. Evidence to support these reports is usually weak. One such report from the the mid-20^th century in Papua New Guinea (PNG) was published by French missionary Father André Pierre Eugène Dupeyratin in his 1962 work, “La Bête et le Papou”, where Dupeyratin describes the capture of a snake reported to be “thirty-one feet and five inches, or ten meters forty-five centimeters” in length.

Here we analyze this report and discuss its relevance. The presence of very large snakes in New Guinea is beyond doubt, several individuals over 4.50 m are known to date. Having observed numerous pythons and anacondas including individuals between 6.7–7.0 m in total length, the last author has become able to estimate approximate total size from the ratio of eye to head. We conclude from photos included in Dupeyrat's report that the snake he described was certainly a large specimen of Simalia amethistina, but its size is unlikely to exceed 6 m, which is certainly a record length for the species but far from being the largest snake in the world.