Idia americalis
In 3 days ~10% in a week ~30%
Idia americalis, the American idia or American snout, is a litter moth of the family Erebidae. The species was first described by Achille Guenée in 1854. It is commonly found in moist forests in North America, ranging from southern Canada to Florida and Texas. It is nocturnal and can be lured by sugar baits and light traps.
The American idia has forewings that range in color from grey to beige or light brown, darker toward the outer margin of the wing, with darker scalloped lines crossing the wings laterally. A dark terminal line is located at the base of the wing's fringe. All have a small bronze or brown spot located near the edge of the forewing. The hindwing is a lighter grey than the forewing and also has darker scalloped lines. Darker specimen can be dark grey or brown. The thorax and abdomen are smoothly scaled and the tibia is hairless. Female antenna are simple while male antenna are biciliate; otherwise, the sexes look similar. The caterpillar is brown with dark brown spots, a black head, and has small white hairs along its sides.
The wingspan ranges from 20 to 30 mm. Adults are on wing from May to October. They can produce two or more broods per year. It can be differentiated from similar species, such as the common idia, by a row of dark marks located on the anterior forewing.
The larvae feed on lichen and detritus, including dead leaves. They may also function as detritivores in ant nests. Adults often feed on lichens attached to tree trunks. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Acadia National Park | 🇺🇸 United States | |
| 2 | Shenandoah National Park | 🇺🇸 United States | |
| 3 | Great Smoky Mountains National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Baltimore | 🇺🇸 United States | |
| 2 | Detroit | 🇺🇸 United States | |
| 3 | Montreal | 🇨🇦 Canada | |
| 4 | Dallas | 🇺🇸 United States | |
| 5 | Toronto | 🇨🇦 Canada | |
| 6 | Boston | 🇺🇸 United States | |
| 7 | Philadelphia | 🇺🇸 United States | |
| 8 | Portland | 🇺🇸 United States | |
| 9 | Washington | 🇺🇸 United States | |
| 10 | Edmonton | 🇨🇦 Canada |
With luck
About 10% of wildlife watchers report an American Idia Moth sighting in Shenandoah National Park on a given day, based on 7 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 447th 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.
May and September–October
In those months about 10% of wildlife watchers report an American Idia Moth in Shenandoah National Park on a given day, against under 5% in June–August and November–April, the lowest months.
Between 9 pm and midnight
Across all the parks we cover, that three-hour window holds the most American Idia Moth 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 American Idia Moth sightings, Shenandoah National Park ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Acadia National Park (United States, about 10%).
GBIF citizen-science records
It is estimated from how often the American Idia Moth is recorded against all the insects logged in Shenandoah 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.
