Terellia ruficauda
In 3 days ~10% in a week ~20%
Terellia ruficauda is a species of fly in the family Tephritidae, the gall flies. It is found in the Palearctic. The larvae feed on Cirsium arvense.. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Toronto | 🇨🇦 Canada |
Rare
Under 5% of wildlife watchers report a Red-Tailed Thistle Fly sighting in Toronto on a given day, based on 11 verified sightings from GBIF citizen-science data. It is the 1005th most-seen of the 1689 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.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Red-Tailed Thistle Fly in Toronto on a given day, so our monthly data shows no clear season.
Only Toronto, in our data
Toronto is the only city on Wallace's Line with enough records to rate Red-Tailed Thistle Fly sightings: under 5% of wildlife watchers there report one on a given day.
Same family: Tephritidae
The closest relatives of the Red-Tailed Thistle Fly that you can see in Toronto (family Tephritidae, Fruit Flies) are Goldenrod Gall Fly (about 10%) and Thistle Stem Gall Fly (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Red-Tailed Thistle Fly is recorded against all the insects logged in Toronto (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.
