Criorhina ranunculi
In 3 days ~10% in a week ~20%
Criorhina ranunculi, is a species of hoverfly found in the spring in many parts of Britain and Europe. The larvae of C. ranunculi are associated with rotting deciduous wood. Adults are remarkable bumblebee mimics and are usually found in woodland in springtime visiting flowers such as sallow to feed.
For terms see Morphology of Diptera Large (wing length 11·25–14 mm.) bumblebee mimic. Thorax and abdomen with long, dense hairs. Hairs black on thorax and basal part of abdomen red or yellowish on tip of abdomen. Scutellar hairs may be pale yellow or brownish. Hind femora considerably thickened, especially in males. Hind tibiae sickle-shaped.
It has a Palaearctic distribution, including southern Norway and Sweden south to central Spain, and from Ireland eastwards through central Europe into European parts of Russia. Habitat includes: Betula, Fagus, and Quercus forest.
Adults are primarily arboreal, but descend to visit flowering shrubs in sun-lit glades. These flies are extremely fast, with a high-pitched whine, zig-zagging between the branches of flowering trees. Flowers visited include Cardamine pratensis, Cornus sanguinea, Crataegus... 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 Large Bearfly sighting in Birmingham on a given day, based on 7 verified sightings from GBIF citizen-science data. It is the 616th 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
In that month about 10% of wildlife watchers report a Large Bearfly in Birmingham on a given day, against under 5% in May to March, the lowest months.
Only Birmingham, in our data
Birmingham is the only city on Wallace's Line with enough records to rate Large Bearfly sightings: under 5% of wildlife watchers there report one on a given day.
Same family: Syrphidae
The closest relatives of the Large Bearfly 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 Large Bearfly is recorded against all the insects logged in Birmingham (7 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.
