Udea prunalis
In 3 days ~10% in a week ~30%
Udea prunalis is a moth of the family Crambidae. It is found in Europe and China (Gansu, Heilongjiang, Ningxia, Shanxi, Sichuan, Xinjiang). The species was first described by Matthew Denis and Ignaz Schiffermüller in 1775. In the Butterfly Conservation's Microlepidoptera Report 2011 this species was classified as common in the UK.
The wingspan is 23–26 mm. The forewings are fuscous-grey with a brownish base. The first line is indistinct, and the second is serrate, blackish, and curved, with a narrow deep sinuation inwards below middle, on dorsum whitish-edged posteriorly. The orbicular and 8-shaped discal spots are darker grey, and the costa posteriorly is spotted darker and sometimes whitish. The hindwings are fuscous-grey, apex darker with two dark fuscous discal dots and a faint second line. The larva is bright deep green with a subdorsal line shining white and a grey-whitish head.
The moth flies from June to August depending on location. The larvae feed on various herbaceous plants, shrubs and deciduous trees. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Snowdonia National Park | 🇬🇧 United Kingdom | |
| 2 | Wadden Sea National Park | 🇩🇪 Germany |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Copenhagen | 🇩🇰 Denmark | |
| 2 | London | 🇬🇧 United Kingdom | |
| 3 | Birmingham | 🇬🇧 United Kingdom | |
| 4 | Helsinki | 🇫🇮 Finland | |
| 5 | Moscow | 🇷🇺 Russia |
With luck
About 10% of wildlife watchers report a Dusky Pearl sighting in Wadden Sea National Park on a given day, based on 19 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 340th most-seen of the 818 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
July and August
In those months about 10% of wildlife watchers report a Dusky Pearl in Wadden Sea National Park on a given day, against under 5% in September to June, the lowest months.
Between 6 and 9 am
Across all the parks we cover, that three-hour window holds the most Dusky Pearl sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 2 parks where we can rate Dusky Pearl sightings, Wadden Sea 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 Pearl is recorded against all the insects logged in Wadden Sea National Park (19 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.
