Adults are commonly 22–30 mm long.
Fine-art photographic collection
Eupholus amalulu semianthracina
A New Guinean weevil wearing a mosaic of light-producing scales over a body that cannot fly away.
About this species
Eupholus amalulu semianthracinaPorion, 1993
Information reviewed15 July 2026
Eupholus amalulu semianthracina is a colour form of a broad-nosed weevil from New Guinea. Like other Eupholus, it is a heavy-bodied leaf feeder with fused wing cases and a surface covered in densely packed optical scales.
Taxonomy
Animalia · Arthropoda · Insecta · Coleoptera · Curculionidae · Eupholus
Accepted taxon. · checked 2026-07-15
Papua New GuineaBroad range and selected reference localities — not a complete occurrence map.
Papua New Guinea
Lowland and foothill rainforest, especially on broad-leaved vines and yam relatives.
Diurnal foliage feeder.
Leaves, especially of tropical vines; larvae feed on roots in soil.
Solitary.
What makes this species remarkable?
The pale blue-grey pattern is made by tiny scales whose internal nanostructure sorts and reflects selected wavelengths, turning the beetle’s cuticle into a field of microscopic optical devices.
The wing cases are fused and the beetle is effectively flightless; its spectacular surface therefore travels through the forest only as fast as six legs can carry it.
Eupholus weevils feed on plants that can contain toxic compounds, and their conspicuous colours are widely interpreted as warning signals advertising an unpleasant meal to predators.