Neuroterus quercusbaccarum
In 3 days ~20% in a week ~40%
The common spangle gall on the underside of leaves and the currant gall on the male catkins or occasionally the leaves, develop as chemically induced distortions on pedunculate oak (Quercus robur), or sessile oak (Quercus petraea) trees, caused by the cynipid wasp Neuroterus quercusbaccarum which has both agamic and bisexual generations.
Previous names or synonyms for this species are Neuroterus baccarum, N. lenticularis, N. malpighii, Cynips lenticularis, C. quercus-baccarum, Spathegaster baccarum, S. varius, S. interruptor. The spangle gall generation on the underside of the oak leaves are flat discs, with a distinct central elevation, slightly hairy, yellow-green at first and reddish later, attached by a short stalk. These galls are up to 6 mm in diameter, unilocular, unilarval with a whitish or yellow undersurface; they mature in September, detach and fall to the ground before the leaves themselves. The larva continue to develop in the fallen spangle and, protected by the leaf layer, they overwinter. Any spangle galls that remain attached to the leaves dry and die.
The smooth surfaced currant gall generation appears in April and lay unfertilised eggs in the staminate... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Snowdonia National Park | 🇬🇧 United Kingdom | |
| 2 | Sierra de Guadarrama National Park | 🇪🇸 Spain | |
| 3 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 4 | Cévennes National Park | 🇫🇷 France |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Liverpool | 🇬🇧 United Kingdom | |
| 2 | London | 🇬🇧 United Kingdom | |
| 3 | Birmingham | 🇬🇧 United Kingdom | |
| 4 | Manchester | 🇬🇧 United Kingdom | |
| 5 | Istanbul | 🇹🇷 Turkey | |
| 6 | Berlin | 🇩🇪 Germany | |
| 7 | Leeds | 🇬🇧 United Kingdom | |
| 8 | Paris | 🇫🇷 France | |
| 9 | Kyiv | 🇺🇦 Ukraine | |
| 10 | Bucharest | 🇷🇴 Romania |
With luck
About 10% of wildlife watchers report a Common Spangle Gall Wasp sighting in Sierra de Guadarrama National Park on a given day, based on 18 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 182nd most-seen of the 597 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
October
In that month about 20% of wildlife watchers report a Common Spangle Gall Wasp in Sierra de Guadarrama National Park on a given day, against under 5% in June–August and December–March, the lowest months.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Common Spangle Gall Wasp sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 4 parks where we can rate Common Spangle Gall Wasp sightings, Sierra de Guadarrama National Park ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Snowdonia National Park (United Kingdom, about 10%).
Same family: Cynipidae
The closest relatives of the Common Spangle Gall Wasp that you can see in Sierra de Guadarrama National Park (family Cynipidae, Gall Wasps) are Andricus quercustozae (about 10%), Mossy Rose Gall Wasp (about 10%) and Oak Apple Gall Wasp (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Common Spangle Gall Wasp is recorded against all the insects logged in Sierra de Guadarrama National Park (18 verified sightings from 2019 to 2026), 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.
