Crambus praefectellus
In 3 days ~20% in a week ~40%
Crambus praefectellus, the common grass-veneer or silver-striped webworm, is a moth of the family Crambidae described by Johann Leopold Theodor Friedrich Zincken in 1821. It is found in the United States and southern Canada east of the Rocky Mountains.
The wingspan is 18–25 mm. Adults are on wing from May to September in the north, from April to October in the mid latitudes and probably year round in southern Florida and Texas. The larvae feed on various grasses and cereal grains. Wikipedia →
| # | Park | Country | Daily sighting probability |
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More parks will be added in future updates.
With luck
About 10% of wildlife watchers report a Common Grass-Veneer sighting in Boston on a given day, based on 82 verified sightings from GBIF citizen-science data. It is the 193rd most-seen of the 1200 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.
June to September
In those months about 10% of wildlife watchers report a Common Grass-Veneer in Boston on a given day, against under 5% in October to May, the lowest months.
Yes
Of the 8 cities where we can rate Common Grass-Veneer sightings, Boston has the highest daily chance: about 10%. Next come Montreal (Canada, under 5%) and Chicago (United States, under 5%).
GBIF citizen-science records
It is estimated from how often the Common Grass-Veneer is recorded against all the insects logged in Boston (82 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.
