Meganeuropsis permiana
| Order | Meganisoptera (Protodonata) |
| Age | ~290 Ma (Early Permian) |
| Wingspan | Up to ~71 cm (28 inches) — largest flying insect ever |
| Diet | Predator |
| Fossil Site | Elmo, Kansas |
| Described | Carpenter, 1939 |
Meganeuropsis permiana holds the record for the largest flying insect that has ever lived. With a wingspan estimated at up to 71 cm, it slightly exceeded even its better-known relative Meganeura. Found in Early Permian deposits in Kansas, Meganeuropsis represents the pinnacle of insect gigantism before declining oxygen levels made such sizes impossible.
Description
Meganeuropsis was built on the same plan as Meganeura — a large, dragonfly-like griffinfly with outstretched wings, large compound eyes, a long abdomen, and raptorial legs. The key difference is size: Meganeuropsis was measurably larger, with the holotype wing fragment indicating a wingspan that slightly exceeded 70 cm. The body length was estimated at over 30 cm.
Discovery
The type specimen was described by Frank Carpenter in 1939 from the Elmo Limestone of Kansas, which is one of the richest Permian insect fossil sites in the world. Additional fragmentary specimens have been found at the same site.
Last of the Giants
Meganeuropsis lived during the Early Permian, when atmospheric oxygen levels were still relatively high (around 30%), though declining from the Carboniferous peak. The Meganisoptera as a group declined through the Permian and went extinct before the Permian-Triassic boundary. The decline in oxygen, combined with the evolution of more agile flying vertebrates and predators, likely contributed to their disappearance. See Oxygen and Gigantism for the full story.