Adults are roughly 15–25 mm long, excluding the visual span of the legs.
Fine-art photographic collection
Sagra oberthuri
A Madagascan leaf beetle with hind legs enlarged into polished, frog-like weapons so extreme that they dominate the whole silhouette.
About this species
Sagra oberthuriJacoby, 1895
Information reviewed15 July 2026
Sagra oberthuri is a metallic Madagascan frog-legged leaf beetle. Males bear massively enlarged hind femora and curved tibiae, while the body itself remains compact and capable of flight.
Taxonomy
Animalia · Arthropoda · Insecta · Coleoptera · Chrysomelidae · Sagra
Accepted taxon. · checked 2026-07-15
MadagascarBroad range and selected reference localities — not a complete occurrence map.
Madagascar
Warm forest and forest edge on climbing or shrubby host plants.
Adults move on foliage and can fly.
Leaves as adults; larvae develop in plant tissue.
Solitary.
What makes this species remarkable?
The male hind femora are expanded far beyond ordinary walking requirements, turning a locomotory limb into a weapon whose size can exceed the visual mass of the body.
The opposing femur and tibia close like a levered clamp; the animal therefore carries two articulated grappling devices while still retaining four ordinary legs for support.
Its mirror-like blue-green surface is created by ordered cuticular optics, so the apparent colour shifts with viewing angle while the underlying shell remains dark.
Sources and scientific references
- GBIF — taxon record/search for Sagra oberthuri
- Catalogue of Life — taxon search for Sagra oberthuri
- Eduard Niga Chrysomelidae gallery — Sagra oberthuri and related frog-legged beetles
- Experimental study of weapon mechanics and locomotor trade-offs in Sagra frog-legged beetles
- Research on self-locking hind-leg weapons in Sagra