Catocala ilia
In 3 days ~10% in a week ~30%
Catocala ilia, the Ilia underwing, beloved underwing or wife underwing, is a moth of the family Erebidae. The species was first described by Pieter Cramer in 1776. It can be found in the eastern part of the United States as well as southern Canada. Subspecies Catocala ilia zoe can be found in California and Arizona.
The wingspan is 65–82 mm. A spot on its forewing with a distinct white circle which encompasses it distinguishes this moth from others in the same family. Otherwise, the forewing can be extremely variable. The underwing that it is named for can range in color from light orange to a deep red. The moths flies from June to September depending on the location.
The larvae feed on oak, including black, burr, red, and white oaks. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 2 | Acadia National Park | 🇺🇸 United States | |
| 3 | Shenandoah National Park | 🇺🇸 United States | |
| 4 | Cumbres de Monterrey National Park | 🇲🇽 Mexico |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Austin | 🇺🇸 United States | |
| 2 | Baltimore | 🇺🇸 United States | |
| 3 | Washington | 🇺🇸 United States | |
| 4 | San Antonio | 🇺🇸 United States | |
| 5 | Houston | 🇺🇸 United States | |
| 6 | Dallas | 🇺🇸 United States | |
| 7 | Boston | 🇺🇸 United States | |
| 8 | Toronto | 🇨🇦 Canada | |
| 9 | New York City | 🇺🇸 United States | |
| 10 | Philadelphia | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report an Ilia Underwing sighting in Shenandoah National Park on a given day, based on 5 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 630th most-seen of the 723 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.
August
In that month about 10% of wildlife watchers report an Ilia Underwing in Shenandoah National Park on a given day, against under 5% in September to July, the lowest months.
Between 8 and 11 pm
Across all the parks we cover, that three-hour window holds the most Ilia Underwing sightings with a recorded time, and about half of them come between 6 am and 6 pm: it is seen both by day and at night.
3rd of 4
Of the 4 parks where we can rate Ilia Underwing sightings, Shenandoah National Park ranks 3rd at under 5%. The best odds are in Great Smoky Mountains National Park (United States, about 10%) and Acadia National Park (United States, about 10%).
GBIF citizen-science records
It is estimated from how often the Ilia Underwing is recorded against all the insects logged in Shenandoah National Park (5 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.
