Chrysops relictus, a horse-fly, has beautiful iridescent eyes, but looks can be deceiving. These flies are blood suckers and are very determined. They have a very painful bite. Only the females suck blood but they will be the ones you'll notice. The males feed on nectar and pollen.

Side view with a better view of the mouthparts of Chrysops.

Part of the Collection of the Insect Portrait Gallery of the Micropolitan Museum © Wim van Egmond