Protoboarmia porcelaria
In 3 days ~20% in a week ~40%
Protoboarmia porcelaria, the porcelain gray or dash-lined looper, is a moth in the Geometrid family found throughout North America, primarily in the east and northwest. The species was first described by Achille Guenée in 1857.
Adults have a wingspan of 27–30 mm. The wings are brown gray and have crossed brown/gray curved lines. At least one of these lines has a small tooth-like dentation along the length. There is a blotch of black at the postmedian start and a discal spot where the antemedian line crosses the costa. The hindwing discal mark is usually in the center.
Mature caterpillars are 25 mm in length and have a distinct Y-pattern on segments one through six. There is only one generation a year in the northern range while there are two in its southern range. The head is gray with a cream colored herringbone pattern on the lobes. The body is slim and is mottled gray and white with a white dorsum.
The female lays around 150 eggs on the foliage of host plants in July. Adults are seen from May to September. The larvae overwinter in their penultimate instar stage. The larvae awaken and begin feeding... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Gros Morne National Park | 🇨🇦 Canada | |
| 2 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 3 | Acadia National Park | 🇺🇸 United States | |
| 4 | Shenandoah National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Philadelphia | 🇺🇸 United States | |
| 2 | Baltimore | 🇺🇸 United States | |
| 3 | Washington | 🇺🇸 United States | |
| 4 | Boston | 🇺🇸 United States | |
| 5 | New York City | 🇺🇸 United States | |
| 6 | Toronto | 🇨🇦 Canada | |
| 7 | Chicago | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Porcelain Gray sighting in Great Smoky Mountains National Park on a given day, based on 20 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 276th most-seen of the 822 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.
May–July and September
In those months about 10% of wildlife watchers report a Porcelain Gray in Great Smoky Mountains National Park on a given day, against under 5% in August and October–April, the lowest months.
Between 10 pm and 1 am
Across all the parks we cover, that three-hour window holds the most Porcelain Gray 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 4 parks where we can rate Porcelain Gray sightings, Great Smoky Mountains National Park ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Gros Morne National Park (Canada, about 10%).
Same family: Geometridae
The closest relatives of the Porcelain Gray that you can see in Great Smoky Mountains National Park (family Geometridae, Geometer Moths) are Tulip-Tree Beauty (about 30%), White-Striped Black (about 20%) and Pale Beauty (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Porcelain Gray is recorded against all the insects logged in Great Smoky Mountains National Park (20 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.
