Portevinia maculata
In 3 days ~10% in a week ~20%
Portevinia maculata, also known as the ramsons hoverfly, is a European species of hoverfly. The adults can be found around Allium species when the plants are in flower (May–June). The larvae tunnel through and overwinter in the bulbs of this plant.
External images For terms see Morphology of Diptera Tergites 2-4 with grey spots. Face very concave for upper two-thirds. Antennae red. See references for determination Palearctic Southern Norway to North Spain. Ireland East into Northern Europe and Central Europe as far as Liechtenstein, Austria and northern Italy.
It can be found in the following countries: Austria, Belgium, Czechia, Denmark, France, Germany, Ireland, Italy, Liechtenstein, Montenegro, Netherlands, Norway, Poland, Romania, Slovakia, Spain, Sweden, Switzerland, Ukraine and the United Kingdom.
Portevinia maculata lives in deciduous woodland glades where Allium ursinum or Allium triquetrum also grow. It can be found at elevations up to 2,000 metres (6,560 ft) above sea level. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Birmingham | 🇬🇧 United Kingdom |
Rare
Under 5% of wildlife watchers report a Portevinia maculata sighting in Birmingham on a given day, based on 11 verified sightings from GBIF citizen-science data. It is the 563rd most-seen of the 811 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 and May
In those months about 10% of wildlife watchers report a Portevinia maculata in Birmingham on a given day, against under 5% in June to March, the lowest months.
Only Birmingham, in our data
Birmingham is the only city on Wallace's Line with enough records to rate Portevinia maculata sightings: under 5% of wildlife watchers there report one on a given day.
Same family: Syrphidae
The closest relatives of the Portevinia maculata that you can see in Birmingham (family Syrphidae, Hover Flies) are Yellow-Haired Sun Fly (about 40%), Marmalade Hover Fly (about 30%) and Tapered Drone Fly (about 30%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Portevinia maculata is recorded against all the insects logged in Birmingham (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.
