Ennomos fuscantaria
In 3 days ~20% in a week ~40%
Ennomos fuscantaria, the dusky thorn, is a moth of the family Geometridae. The species can be found in the western part of the Palearctic realm in western Europe and from central Scandinavia its range extends to the northern Mediterranean and east to Russia.
The wingspan is 35–40 mm. The ground colour is ochre yellow. There are violet-grey flecks on the forewing and an oblong discal spot. The fasciae (bands) are grey brown. On the hindwing the grey brown transverse line hides a small discal spot.
Other Ennomos species are similar. The moth is on wing from July to October depending on the location. The caterpillars feed on ash (Fraxinus excelsior), but also privet (Ligustrum species) and other shrubs. 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 |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Liverpool | 🇬🇧 United Kingdom | |
| 2 | London | 🇬🇧 United Kingdom | |
| 3 | Birmingham | 🇬🇧 United Kingdom | |
| 4 | Manchester | 🇬🇧 United Kingdom | |
| 5 | Leeds | 🇬🇧 United Kingdom | |
| 6 | Essen | 🇩🇪 Germany | |
| 7 | Copenhagen | 🇩🇰 Denmark |
With luck
About 10% of wildlife watchers report a Dusky Thorn 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 197th 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.
June–July and September–October
In those months about 10% of wildlife watchers report a Dusky Thorn in Sierra de Guadarrama National Park on a given day, against under 5% in August and November–May, the lowest months.
Between 10 pm and 1 am
Across all the parks we cover, that three-hour window holds the most Dusky Thorn sightings with a recorded time, and about 6 in 10 of them come between 6 pm and 6 am: it is seen both by day and at night.
Among the best
Of the 3 parks where we can rate Dusky Thorn 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%).
GBIF citizen-science records
It is estimated from how often the Dusky Thorn 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.
