Urophora quadrifasciata
In 3 days ~10% in a week ~20%
Urophora quadrifasciata is a species of tephritid or fruit flies in the genus Urophora of the family Tephritidae. The host plant for the larvae is usually a knapweed (Centaurea sp), and because of this, it is used to control Centaurea stoebe. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Berlin | 🇩🇪 Germany | |
| 2 | London | 🇬🇧 United Kingdom | |
| 3 | Toronto | 🇨🇦 Canada | |
| 4 | Washington | 🇺🇸 United States | |
| 5 | New York City | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Four-Barred Knapweed Gall Fly sighting in Berlin on a given day, based on 11 verified sightings from GBIF citizen-science data. It is the 646th most-seen of the 1065 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
July and August
In those months about 10% of wildlife watchers report a Four-Barred Knapweed Gall Fly in Berlin on a given day, against under 5% in September to June, the lowest months.
Yes
Of the 5 cities where we can rate Four-Barred Knapweed Gall Fly sightings, Berlin has the highest daily chance: under 5%. Next come London (United Kingdom, under 5%) and Toronto (Canada, under 5%).
GBIF citizen-science records
It is estimated from how often the Four-Barred Knapweed Gall Fly is recorded against all the insects logged in Berlin (11 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.
