Hover or syrphid fly
Pests eaten:
aphids and other soft-bodied insects
Some favorite plants:
caraway, fennel, goldenrod, dill, coriander, Queen Anne's lace, buckwheat, fernleaf yarrow, golden chamomile, cosmos 'White sensation', marigold 'Lemon gem', and cornflower
Description:
Hoverfly larva are small caterpillars that vary in color but typically have a yellow stripe running from head to tail. They have a tapered head, no legs and see-through skin allowing a view of their internal organs. The adults look like a long thin bee with yellow and black stripes and a relatively large head ranging in size from 1/4 to 3/4 inch long. If you watch them for a bit, you will see them hover in the air around flowers as in the video below, titled "Hoverfly". The hoverfly larva feed on prey while the adult hoverflies feed on pollen and nectar.
YouTube videos:
Eating pollen (hoverfly)
Hoverfly
Resources:
UC IPM Online
Agri-Life Extension