Cydia splendana
In 3 days ~20% in a week ~40%
Cydia splendana, the chestnut tortrix, is a moth of the family Tortricidae. It is found in Europe. It is also known as the acorn moth, but this can also refer to Blastobasis glandulella from North America, which belongs to the more primitive family Blastobasidae.
The wingspan is 12–16 mm. The moth flies from May to September depending on the location. The larvae feed on oak and sweet chestnut, and perhaps also Juglans species. The larvae develop mostly in mature chestnut fruits. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Wadden Sea National Park | 🇩🇪 Germany | |
| 2 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 3 | Cévennes National Park | 🇫🇷 France | |
| 4 | Pyrénées National Park | 🇫🇷 France |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Liverpool | 🇬🇧 United Kingdom | |
| 2 | London | 🇬🇧 United Kingdom | |
| 3 | Birmingham | 🇬🇧 United Kingdom | |
| 4 | Rotterdam [The Hague] | 🇳🇱 Netherlands | |
| 5 | Manchester | 🇬🇧 United Kingdom | |
| 6 | Berlin | 🇩🇪 Germany | |
| 7 | Essen | 🇩🇪 Germany | |
| 8 | Porto | 🇵🇹 Portugal | |
| 9 | Helsinki | 🇫🇮 Finland | |
| 10 | Paris | 🇫🇷 France |
With luck
About 10% of wildlife watchers report a Marbled Piercer sighting in London on a given day, based on 167 verified sightings from GBIF citizen-science data. It is the 262nd most-seen of the 1504 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.
August
In that month about 20% of wildlife watchers report a Marbled Piercer in London on a given day, against under 5% in October to June, the lowest months.
Between 10 pm and 1 am
Across all the parks we cover, that three-hour window holds the most Marbled Piercer sightings with a recorded time, and about 7 in 10 of them come between 6 pm and 6 am: it is mostly seen at night.
Among the best
Of the 10 cities where we can rate Marbled Piercer sightings, London ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Liverpool (United Kingdom, about 10%).
GBIF citizen-science records
It is estimated from how often the Marbled Piercer is recorded against all the insects logged in London (167 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.
