On this page, Overview - mimicry - food and behaviour - hover fly eggs - hoverfly larvae - related pages
There are 6,000 species of hoverfly world wide, and 276 species in the U. K. The adults are often brightly coloured attractive flies. Note the the aristate antennae (see photographs below) and huge eyes typical of the more "advanced" flies.
Above is an aphid-eating hoverfly larva. It has stuck the skins of sucked-dry aphids to its body - they are the little white things on the centre of its body. A larva like this can eat 50 aphids a day.
When the larva pupates the pupa is brown and stuck to the plant or some other surface, see the photograph below.
There are also aquatic larva, like the rat-tailed maggot below, they tend to pupate near the water.
The eggs are usually white. Eggs that hatch into carnivorous larvae are usually glued singly to plants amongst or near their prey. Eggs of non-carnivorous species are usually laid in batches on or near the larval food.
Many hoverflies mimic the colouration and/or hairiness of social bees and wasps. This enables them to avoid attack by predators who believe they might be able to sting. This form of mimicry is termed Batesian mimicry.
Many Hover fly larvae are slug-like and eat aphids (see above), others are scavengers.
Adult hover flies feed on pollen and nectar, so are valuable pollinators.
Flight speed has been recorded as 3.5 metres per second with a wing beat of 120 per second. Compare this with other insects.
The photograph on the below shows mate seeking behaviour. The male hoverfly generally has two strategies in seeking a mate.
The African water lily on its first day of blooming has hundreds of showy stamens and a nice bright flower. This attracts hover flies.
On day 1 in the centre of the flower is a pool of poisonous liquid that looks like nectar. When the hover fly lands on the stamen it falls into this liquid as the stamen are very smooth and overhang the pool. The hover fly cannot climb out as there is nothing to get a grip on. So the hover fly dies in the poisonous liquid.
At night the flower closes and the liquid washes pollen from day two water lilies off the body of the dead hover fly. This pollen fertilises eggs at the bottom of the liquid. On day two it is quite safe for hover flies to visit the lily as the stamens no longer hang over a poisonous pool as the pool has gone. The hover flies will gather pollen on their bodies, but will pay with their lives if they then try to do the same to a day one flower.