Eresia nauplius
In 3 days ~20% in a week ~40%
Eresia nauplius, the Peruvian crescent or Nauplius crescent, is a butterfly of the family Nymphalidae. It was described by William Chapman Hewitson in 1852. It is found in most of the Amazon region. The habitat consists of forest edges with low vegetation, including river banks, forest clearings, glades and roadsides.
The wingspan is about 45 mm. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Manu National Park | 🇵🇪 Peru | |
| 2 | Tambopata National Reserve | 🇵🇪 Peru | |
| 3 | Yasuní National Park | 🇪🇨 Ecuador |
With luck
About 10% of wildlife watchers report a Nauplius Crescent sighting in Yasuní National Park on a given day, based on 7 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 140th most-seen of the 203 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.
July–August and October
In those months about 20% of wildlife watchers report a Nauplius Crescent in Yasuní National Park on a given day, against under 5% in February–June, September and December, the lowest months.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Nauplius Crescent 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 3 parks where we can rate Nauplius Crescent sightings, Yasuní National Park ranks 3rd at about 10%, level with the leaders once rounded. The best odds are in Manu National Park (Peru, about 10%) and Tambopata National Reserve (Peru, about 10%).
GBIF citizen-science records
It is estimated from how often the Nauplius Crescent is recorded against all the insects logged in Yasuní National Park (7 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.
