Melangyna umbellatarum
In 3 days ~10% in a week ~20%
Melangyna umbellatarum is a Holarctic species of hoverfly. External images For terms, see: Morphology of Diptera. Wing length: 6.5–8.75 mm (0.256–0.344 in). This species closely resembles Melangyna ericarum, but the thorax has pale hairs on the disc (many black hairs in M. ericarum). The jowls have only pale hairs below the eyes, whereas M. ericarum has some black hairs. Tergite 2 has moderately large, yellow side-spots which extend close to or over the side-margins of the tergite (they are widely set back from it in M. ericarum). The legs have distinct clear orange markings (obscure in M. ericarum), and the four anterior femora have few or none of the posterior black bristles present in M. ericarum. For full characters and references, see Bartsch et al. and Bei-Bienko, G.Y. & Steyskal, G.C. The male terminalia are figured by Hippa.
Palearctic: Fennoscandia south to Iberia, Ireland east through North Europe, Central Europe and South Europe then east into European Russia and Siberia to Kamchatka. Nearctic: Alaska to Arizona (records may be referable to M. fisherii (Walton).
Habitat: streams with Salix, Salix carr, beside streams and... Wikipedia →
| # | Park | Country | Daily sighting probability |
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More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | London | 🇬🇧 United Kingdom |
Rare
Under 5% of wildlife watchers report a Bare-Winged Halfband sighting in London on a given day, based on 6 verified sightings from GBIF citizen-science data. It is the 1300th most-seen of the 1504 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 Bare-Winged Halfband in London on a given day, so our monthly data shows no clear season.
Only London, in our data
London is the only city on Wallace's Line with enough records to rate Bare-Winged Halfband sightings: under 5% of wildlife watchers there report one on a given day.
Same family: Syrphidae
The closest relatives of the Bare-Winged Halfband that you can see in London (family Syrphidae, Hover Flies) are Yellow-Haired Sun Fly (about 40%), Marmalade Hover Fly (about 30%) and Hornet Mimic Hover Fly (about 30%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Bare-Winged Halfband is recorded against all the insects logged in London (6 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.
