Common name: Flower fly, Syrphid fly, Syrphidae
Scientific name: Eristalis spp., Volucella spp.
Aphids, thrips, psyllids, scale insects, small caterpillars, and larvae of Heliotes
Eggs are tiny, about 1mm in size, ovate-shaped, and glistening-white. These are found laid singly and close to the developing aphid colony in the leaves, shoots, or stems of the plants. They hatch within 2-3 days.
The larvae, known as Syrphids, are legless slug like maggots, about 1-13 mm in length depending on their larval stages. They usually have a mottled-gray, beige, or light-green color. They lift their pointed heads to look for preys. Once preys are located, their
mouthparts suck out the contents of the preys. Larvae are frequently found feeding on aphids in the sheltered and curled portion of leaves. They blend well with their habitat and therefore they must be looked for closely to locate them.
Pupae are teardrops shaped and are found in the soil surface or in the plant's foliage.
Adult hoverflies are true flies with only two wings instead of four which most insects have. Adults are large and beautiful insects about 13 mm long. They have a dark head, a dark thorax, and a banded yellow and black abdomen. They closely resemble bees or wasps rather than flies. Their habit of hovering like humming birds gave them the names hoverflies or flower flies. They are expert hoverers, able to remain absolutely stationary in midair. In some species, males will hover in certain spots to attract the attention of females while other species patrol a wider area of up to 100 yards to feed and mate. They dart from flower to flower making them easy to
distinguish from the bees and wasps. They feed on pollen, nectar, and honeydew. They are good pollinators.
Hoverflies are attracted to all flowering plants but even more so to small-flowered herbs like wild mustard, coriander, dill, lupins, sunflower, and fennel. It is advisable to have multiple crops as adults basically feed on pollen and nectar and it is advisable to allow flowering weeds such as wild carrot and yarrow to grow between crop plants.
Hoverflies' larvae are most noticeable in the latter half of the growing season when aphids are established.
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- Teetes, G.; Pendleton, B. (1999): Insect pests of sorghum. Department of Entomology. Texas A&M University.
- Yepsen, R. Editor. (1984): The encyclopedia of natural insect and disease control. Rodale Press, Emmaus, PA.