Selenia dentaria
In 3 days ~40% in a week ~70%
Selenia dentaria, the early thorn, is a moth of the family Geometridae. It is found in Northern Europe, and across the Palearctic to the Caucasus, Transcaucasia, North Siberia, Russian Far East, Amur and Mongolia. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Snowdonia National Park | 🇬🇧 United Kingdom | |
| 2 | Wadden Sea National Park | 🇩🇪 Germany | |
| 3 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 4 | Pyrénées National Park | 🇫🇷 France |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Porto | 🇵🇹 Portugal | |
| 2 | Manchester | 🇬🇧 United Kingdom | |
| 3 | Liverpool | 🇬🇧 United Kingdom | |
| 4 | Birmingham | 🇬🇧 United Kingdom | |
| 5 | London | 🇬🇧 United Kingdom | |
| 6 | Leeds | 🇬🇧 United Kingdom | |
| 7 | Copenhagen | 🇩🇰 Denmark |
Possible
About 20% of wildlife watchers report an Early Thorn sighting in Snowdonia National Park on a given day, based on 31 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 61st most-seen of the 387 insects we can rate there. Over three days the chance rises to about 40%, and over a week to about 70%, if each day is a fresh chance.
March
In that month about 40% of wildlife watchers report an Early Thorn in Snowdonia National Park on a given day, against under 5% in May–June and September–February, the lowest months.
Between 11 pm and 2 am
Across all the parks we cover, that three-hour window holds the most Early Thorn sightings with a recorded time, and about half of them come between 6 pm and 6 am: it is seen both by day and at night.
Yes
Of the 4 parks where we can rate Early Thorn sightings, Snowdonia National Park has the highest daily chance: about 20%. Next come Wadden Sea National Park (Germany, about 10%) and Bavarian Forest National Park (Germany, about 10%).
Same genus: Selenia
The closest relatives of the Early Thorn that you can see in Snowdonia National Park (genus Selenia) are Purple Thorn (about 10%) and Lunar Thorn (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Early Thorn is recorded against all the insects logged in Snowdonia National Park (31 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.
