Tetracis cachexiata
In 3 days ~10% in a week ~20%
Tetracis cachexiata, the white slant-line or white slaut, is a moth of the family Geometridae. The species was first described by Achille Guenée in 1858. It is found in North America from Nova Scotia to central British Columbia, south to northern Florida and west to Montana and northern Colorado.
The length of the forewings 19–26 mm. Adults are on wing from May to early July. The larvae feed on various plants including Alnus, Betula, Prunus, Salix, Tilia, Ulmus, Viburnum, Abies, Larix, Pinus, and Tsuga species. 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 |
Rare
Under 5% of wildlife watchers report a White Slant-Line sighting in Boston on a given day, based on 12 verified sightings from GBIF citizen-science data. It is the 668th most-seen of the 1200 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
June
In that month about 10% of wildlife watchers report a White Slant-Line in Boston on a given day, against under 5% in July to May, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most White Slant-Line sightings with a recorded time, and about 6 in 10 of them come between 6 am and 6 pm: it is seen both by day and at night.
Among the best
Of the 3 cities where we can rate White Slant-Line sightings, Boston ranks 2nd at under 5%, level with the leaders once rounded. The best odds are in Toronto (Canada, under 5%).
Same family: Geometridae
The closest relatives of the White Slant-Line that you can see in Boston (family Geometridae, Geometer Moths) are Pale Beauty (about 10%), Single-Dotted Wave (about 10%) and Winter Moth (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the White Slant-Line is recorded against all the insects logged in Boston (12 verified sightings), 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.
