Syrphid Fly – Syritta pipiens


Syrphid Fly – Syritta pipiens
Order Diptera | Family Syrphidae – Flower Flies, Hover Flies

Live adult flower flies photographed in the wild at Allegheny National Forest, Pennsylvania
Insects & Spiders | Flies Index | Tachinidae | Dung Flies | Bee Flies | Robber Flies

Syrphid Fly - Syritta pipiens

The hover flies are a large group of generally beneficial insects. Their coloring and movements of most species mimic bees or wasps — they are either stout-bodied and covered with hair, resembling a bumble bee, or boldly patterned with yellow, orange and black, resembling wasps or honey bees. Some species even go so far as to wave their front legs in front of their face to mimic the jointed antennae of the potter wasps. Adult hover flies can generally be found hovering in midair or feeding at flower blossoms. They eat only nectar and pollen. However, their larvae can be rapacious predators of aphids, thrips, and mites, or parasitic in the nests of ants or solitary bees. Still other larvae scavenge in soil or decaying plant material or eat living plants. Some are aquatic.

Syrphid flies are routinely used as a biological control in the lettuce fields of California's vegetable-producing regions, where the fly's larvae are generally effective in controlling lettuce aphid (Nasonovia ribisnigri). It is primarily the Syrphidae that enable organic romaine growers on California's central coast to produce harvestable crops.

Syrphidae larvae are, in turn, parasitized by wasps in the Hymenoptera families Ichneumonidae and Pteromalidae [1].

Syrphid Fly - Syritta pipiens
One indicator of the species is the sawtooth spines on the underside of the enlarged femora

Quite a few flower fly species' larvae feed on aphids (aphidophagous). All are in the subfamily Syrphinae. Common aphidophagous flower flies in California vegetable crops include Toxomerus marginatus, Allograpta obliqua, Syrphus opinator among many others [1].

Syritta pipiens lateral view

References

  1. University of California, DANR, "Biological Control Agents for Aphids in Vegetable Crops"
Flies of North America – Order Diptera. Flies are prevalent in virtually all habitats, with over 16,000 species in North America. Flies can be distinguished from all other insects in that they only have one pair of normal wings. Most flies have compound eyes and mouthparts adapted for piercing, lapping or sucking fluids.
Syrphidae | Flies Index | Tachinidae | Bee Flies | Robber Flies