Andricus foecundatrix
In 3 days ~30% in a week ~60%
Andricus foecundatrix (formerly Andricus fecundator) is a parthenogenetic gall wasp which lays a single egg within a leaf bud, using its ovipositor, to produce a gall known as an oak artichoke gall, oak hop gall, larch-cone gall or hop strobile. The gall develops as a chemically induced distortion of leaf axillary or terminal buds on pedunculate oak (Quercus robur) or sessile oak (Quercus petraea) trees. The larva lives inside a smaller hard casing inside the artichoke and this is released in autumn. The asexual wasp emerges in spring and lays her eggs in the oak catkins. These develop into small oval galls which produce the sexual generation of wasps. A yew artichoke gall caused by the fly Taxomyia taxi also exists, but is unrelated to the oak-borne species. Previous names or synonyms for the species A. fecundator are A. fecundatrix, A. pilosus, A. foecundatrix (see below), A. gemmarum, A. gemmae, A. gemmaequercus, A. gemmaecinaraeformis and A. quercusgemmae.
The scientific name is now once again Andricus foecundatrix. Young galls exhibit a tuft of long hairs protruding from the centre of the 'artichoke', the remainder being overlapping scales. The hairs are attached to... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Snowdonia National Park | 🇬🇧 United Kingdom | |
| 2 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 3 | Sierra de Guadarrama National Park | 🇪🇸 Spain | |
| 4 | Wadden Sea National Park | 🇩🇪 Germany |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Liverpool | 🇬🇧 United Kingdom | |
| 2 | Manchester | 🇬🇧 United Kingdom | |
| 3 | Birmingham | 🇬🇧 United Kingdom | |
| 4 | London | 🇬🇧 United Kingdom | |
| 5 | Leeds | 🇬🇧 United Kingdom | |
| 6 | Berlin | 🇩🇪 Germany | |
| 7 | Prague | 🇨🇿 Czechia | |
| 8 | Warsaw | 🇵🇱 Poland | |
| 9 | Munich | 🇩🇪 Germany | |
| 10 | Porto | 🇵🇹 Portugal |
With luck
About 10% of wildlife watchers report an Oak Artichoke Gall Wasp sighting in Snowdonia National Park on a given day, based on 17 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 138th most-seen of the 387 insects we can rate there. Over three days the chance rises to about 30%, and over a week to about 60%, if each day is a fresh chance.
December
In that month about 30% of wildlife watchers report an Oak Artichoke Gall Wasp in Snowdonia National Park on a given day, against under 5% in February, April–May and November, the lowest months. That is one of Snowdonia National Park's wettest months, with about 240 mm of rain against 95 mm in April.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Oak Artichoke 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.
Yes
Of the 4 parks where we can rate Oak Artichoke Gall Wasp sightings, Snowdonia National Park has the highest daily chance: about 10%. Next come Bavarian Forest National Park (Germany, about 10%) and Sierra de Guadarrama National Park (Spain, under 5%).
GBIF citizen-science records
It is estimated from how often the Oak Artichoke Gall Wasp is recorded against all the insects logged in Snowdonia National Park (17 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.
