Missouri Master Naturalists- Springfield Plateau Chapter

Sunday, December 12, 2021

Long-legged Fly


Last May I got this photograph of a long-legged fly from Courtney Reece of the WOLF School.  We now have "research grade" confirmation on INaturalist that it is Condylostylus longicornis, possibly the most wide spread species in its genus, found from the US down to Paraguay and even Polynesia!

Head on - Ken Schneider CC
Long-legged flies range in size from 1 to 9 mm and are usually a shining metallic color ranging from green to blue to bronze. They are generally characterized by their slender bodies and long legs.

They are commonly found in moist woodland areas.  Larvae develop in wet to dry soil and pupate in cocoons made up of soil particles cemented together. The larvae are predators, feeding on soil or bark-dwelling invertebrates.  Adults mate after elaborate and unique behavior, involving the males displaying their legs to the female.  Bugguide

Long-legged flies belong to the family Dolichopodidae (try saying that three times rapidly!) which has thousands of species worldwide.  Typically they have large, prominent eyes and a metallic cast to their appearance.

"Long-legged flies (Figure 1) are small (1-9 mm), but easy to recognize because of their metallic green, blue or gold coloration, slender body shape, and not surprisingly, rather long legs! Often you can find them scurrying about on vegetation in the sunlight during the day. They are excellent fliers, but usually run or fly short distances from leaf to leaf when disturbed, making them a lot of fun to observe in your own backyard!"

They are considered beneficial for pest control, feeding on small arthropods, including other flies, thrips, aphids, mites, springtails, leafhoppers, whiteflies, beetle larvae, and even termites! They will carry their prey around with them in flight as they secrete digestive enzymes into it and ingest the liquefied contents (similar to spiders). Ohioline.osu

Ready to pronounce Dolichopodidae? Here you go!