Andricus foecundatrix
In 3 days ~30% in a week ~50%
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 London on a given day, based on 157 verified sightings from GBIF citizen-science data. It is the 223rd most-seen of the 1504 insects we can rate there. Over three days the chance rises to about 30%, and over a week to about 50%, if each day is a fresh chance.
September
In that month about 20% of wildlife watchers report an Oak Artichoke Gall Wasp in London on a given day, against under 5% in May–June and December, the lowest months.
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.
Among the best
Of the 13 cities where we can rate Oak Artichoke Gall Wasp sightings, London ranks 4th at about 10%, level with the leaders once rounded. The best odds are in Liverpool (United Kingdom, about 10%), Manchester (United Kingdom, about 10%) and Birmingham (United Kingdom, about 10%).
Same genus: Andricus
The closest relatives of the Oak Artichoke Gall Wasp that you can see in London (genus Andricus) are Knopper Gall Wasp (about 20%), Oak Marble Gall Wasp (about 20%) and Ram's Horn Gall Wasp (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Oak Artichoke Gall Wasp is recorded against all the insects logged in London (157 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.
