Argyresthia thuiella
In 3 days ~10% in a week ~20%
Argyresthia thuiella, the arborvitae leafminer, thuja mining moth or American thuja shoot moth, is a moth of the family Argyresthiidae. It is found in southeastern Canada and the northeastern United States to North Carolina, west to Missouri, north to Manitoba. In Maine, they are one of several arborvitae or cedar leafminer moth species damaging eastern white cedar (Thuja occidentalis) in the region, including Argyresthia aureoargentella, Argyresthia canadensis, and Coleotechnites thujaella. There is also an isolated population in British Columbia. The species is also present in Europe, where it has been introduced on three occasions: to the Netherlands in 1971, Germany in 1975 and Austria in 1976.
The wingspan is about 8 mm. Adults are on wing from May to July depending on the location. The larvae feed on the leaves of Thuja occidentalis as well as other arborvitae and false cypress (Chamaecyparis) species. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
Rare
Under 5% of wildlife watchers report an Arborvitae Leafminer sighting in Toronto on a given day, based on 26 verified sightings from GBIF citizen-science data. It is the 612th most-seen of the 1689 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 an Arborvitae Leafminer in Toronto on a given day, against under 5% in July to May, the lowest months.
Yes
Of the 2 cities where we can rate Arborvitae Leafminer sightings, Toronto has the highest daily chance: under 5%. Next come Montreal (Canada, under 5%).
GBIF citizen-science records
It is estimated from how often the Arborvitae Leafminer is recorded against all the insects logged in Toronto (26 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.
