Knapweed Gall Weevil vs Two-coloured Mason Bee

Side-by-side species comparison

Attribute Knapweed Gall Weevil Two-coloured Mason Bee
Scientific Name Bangasternus fausti Osmia bicolor
Order Coleoptera Hymenoptera
Family Curculionidae Megachilidae
Size 4-6 mm 8-11 mm
Habitat Grasslands Grasslands
Diet Gall Makers Nectar Feeders
Regions Europe, Central Asia Europe
Conservation Least Concern Least Concern

Knapweed Gall Weevil

A weevil that induces galls in knapweed flower heads. Larvae develop inside the enlarged flower buds. Used in biological control of invasive knapweeds in North America.

💡

Did You Know?

Released in North America as biocontrol for invasive spotted knapweed, which costs ranchers millions annually.

Two-coloured Mason Bee

A distinctive bee with a black head and thorax and bright orange abdominal hair. It uniquely nests inside empty snail shells on chalk grasslands.

💡

Did You Know?

After filling a snail shell with pollen and eggs, the female camouflages it by piling grass and plant stems over it.