Syrphus vitripennis
In 3 days ~10% in a week ~20%
Syrphus vitripennis is a very common European and North American species of hoverfly. Its larvae feed on aphids For terms see Morphology of Diptera Wing length 7·25-10·25 mm. Frons above lunulae black. Tergites 3 and 4 with entire yellow bands and lateral margin of tergites black. Male: femora 3 black for basal three-quarters. Female: femora 3 black on basal two-thirds. The male genitalia and the larva are figured by Dusek and Laska (1964). See references for determination.
Palearctic throughout. Nearctic Alaska to California. Migratory. Habitat: Deciduous and coniferous woodland and anthropophilic, occurring along field hedges, in suburban gardens and parks. Flies March to October. Wikipedia →
| # | Park | Country | Daily sighting probability |
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More parks will be added in future updates.
Rare
Under 5% of wildlife watchers report a Black-Thighed Flower Fly sighting in Paris on a given day, based on 5 verified sightings from GBIF citizen-science data. It is the 827th most-seen of the 916 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.
April
In that month about 10% of wildlife watchers report a Black-Thighed Flower Fly in Paris on a given day, against under 5% in May to March, the lowest months.
Among the best
Of the 2 cities where we can rate Black-Thighed Flower Fly sightings, Paris ranks 2nd at under 5%, level with the leaders once rounded. The best odds are in Berlin (Germany, under 5%).
GBIF citizen-science records
It is estimated from how often the Black-Thighed Flower Fly is recorded against all the insects logged in Paris (5 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.
