Delphinia picta
In 3 days ~20% in a week ~50%
Delphinia picta is a species of picture-winged fly in the family Ulidiidae. The specific name picta is from Latin and means "painted". It is the only species in the monospecific genus Delphinia. It is found in the United States on the East Coast and in the Midwest from Florida to Maine across to Kansas through Minnesota but also can be found in Mexico and El Salvador. It is sometimes mistaken for a species of fruit fly, but D. picta do not feed on living plant matter, as they are detritivores and eat decaying plant matter. They also have been observed eating fermenting frass from Megacyllene robiniae on black locust trees. They can be found almost anywhere there is decaying vegetation: landfills, temperate deciduous forests, swamps, and even shaded fields.
The best way to identify the species is by the distinct pattern on its wings, which are shiny and dark brown with a hyaline background. Its body is about 7mm long with a black abdomen and a light brown head, thorax, and legs. The ovipositor averages 1.27mm long with two dorsal and one ventral prominent pairs of setae, as well as many short setae on both sides. The tip of the ovipositor also has a slight bend downward... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Shenandoah National Park | 🇺🇸 United States | |
| 2 | Great Smoky Mountains National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Detroit | 🇺🇸 United States | |
| 2 | Baltimore | 🇺🇸 United States | |
| 3 | Philadelphia | 🇺🇸 United States | |
| 4 | Washington | 🇺🇸 United States | |
| 5 | New York City | 🇺🇸 United States | |
| 6 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 7 | Dallas | 🇺🇸 United States | |
| 8 | Chicago | 🇺🇸 United States | |
| 9 | Boston | 🇺🇸 United States | |
| 10 | Austin | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Common Picture-Winged Fly sighting in Chicago on a given day, based on 275 verified sightings from GBIF citizen-science data. It is the 59th most-seen of the 978 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 50%, if each day is a fresh chance.
June
In that month about 20% of wildlife watchers report a Common Picture-Winged Fly in Chicago on a given day, against under 5% in October to April, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Common Picture-Winged Fly sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 15 cities where we can rate Common Picture-Winged Fly sightings, Chicago ranks 8th at about 10%, level with the leaders once rounded. The best odds are in Detroit (United States, about 10%), Baltimore (United States, about 10%) and Philadelphia (United States, about 10%).
GBIF citizen-science records
It is estimated from how often the Common Picture-Winged Fly is recorded against all the insects logged in Chicago (275 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
