Most beetles, including most buprestids, fly with their elytra held out and vibrating their hindwings to give lift and thrust.
Acmaeodera, however, fly with their hind wings only — the elytra are fused down the center and form a shield over the insect's abdomen, even during flight. This fact, combined with the banding across the abdomen which is common (though not universal) in this genus, gives many of them a distinct wasp-like appearance when in flight.
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