Condylostylus purpureus

Identification to species within Condylostylus requires examination of male genitalia. The species can be distinguished from other dolichopodid genera by the combination of: body form typical of Condylostylus (elongate with long legs), metallic coloration, and habitat use (darting over leaves in sunny spots rather than skating on water or running on tree trunks). Separation from other Condylostylus species requires detailed morphological study.

Small fly, likely with metallic coloration (purple, green, copper, or bronze based on genus characteristics and species epithet). Members of Condylostylus typically have the elongated body form and extremely long legs characteristic of Dolichopodidae. Males possess claspers and other genital appendages that protrude forward at the tip of the abdomen. Body length likely falls within the 1–10 mm range typical for the family, with most Condylostylus species being 5 mm or less.

Found in gardens, along forest edges, and similar open habitats with sunny conditions. Typical of Condylostylus species that occur on foliage rather than on water surfaces or tree trunks.

Recorded from Illinois (Skokie) based on photographic documentation. The genus Condylostylus is widespread in North America.

Adults are predatory on other small insects, capturing prey using modified mouthparts with an extendable lower lip equipped with opposable lobes for crushing or tearing prey.

Larval biology unknown for this species. Dolichopodid larvae are generally predatory; most are aquatic or semi-aquatic, though some terrestrial larvae occur in other genera.

Adults are active, fast-moving predators that rarely stop moving. They dart over leaves in sunny spots and are sensitive to disturbance, often fleeing when approached. Like other long-legged flies, they likely engage in complex courtship displays involving visual signals.

Adult predators that help regulate populations of small insects. May serve as prey for larger predatory insects, spiders, and other arthropods.

Potential beneficial insect in gardens as a predator of pest insects. Subject of interest to macrophotographers, though their activity makes them challenging subjects.

• Other Condylostylus speciesRequire examination of male genitalia for definitive separation; many share similar metallic coloration and habitat preferences.
• Dolichopus speciesAlso metallic long-legged flies, but males typically have modified front tarsi with scale-like ornaments for courtship display; Condylostylus lacks these front leg modifications.
• Hydrophorus speciesSkate on water surfaces rather than occurring on foliage; have different habitat use and leg proportions adapted for surface locomotion.
• Medetera speciesOccur on tree trunks in characteristic "tiptoe" posture; have shorter legs relative to body and different foraging behavior.

• Diptera
• Dolichopodidae
• predator
• metallic
• long-legged fly

• BugGuide
• GBIF taxonomy match
• Catalogue of Life
• Brachys on oak | Beetles In The Bush
• Bug Eric: Long-legged Flies
• Some recent publications | Beetles In The Bush