Bug FAQDouble Square-spot
Xestia triangulum · Order: Lepidoptera · Family: Noctuidae
Also called: Square-spotted Clay
The double square-spot moth has a wingspan of about 1.4 to 1.8 inches and pale brown forewings with two distinct black marks. It lives on forest edges, shrub-covered slopes, heaths, gardens and parkland across most of Europe and eastward through the Palearctic to Siberia and Iran.
Source: Wikipedia
How to recognize it
Forewings are grey-brown with a rufous tint, showing a small basal blotch, a pre-apical costal spot and a prominently black-brown cell; hindwings are dark brown. The forewings also display two distinctive black marks on a pale brown background.
Source: Wikipedia
Size
Wingspan ranges from 36 to 46 mm (about 1.4 to 1.8 in).
Source: Wikipedia
Where it lives
Found mainly on forest edges, shrub-covered slopes, heaths, gardens and parkland.
Source: Wikipedia
What it eats
Larvae are ochreous brown, speckled with black and have pale lines with dark sub-dorsal bars.
Source: Wikipedia
Life cycle
The species overwinters in the larval stage.
Source: Wikipedia
When you see it
Adults fly at night during June and July in the British Isles.
Source: Wikipedia
Where it comes from
Distributed through most of Europe, excluding Mediterranean islands and the far north of Fennoscandia. Its eastern range extends across the Palearctic to Siberia and south-east to the Black Sea region and Iran.
Source: Wikipedia
Lookalikes
It is very similar to Xestia ditrapezium. Xestia ditrapezium typically has narrower (or longer) forewings.
Source: Wikipedia
More photos
Questions people ask
How can I tell it apart from Xestia ditrapezium?
Xestia ditrapezium usually has narrower (or longer) forewings compared with the double square-spot.
Source: Wikipedia
Where is this moth found?
It occurs across most of Europe, avoiding Mediterranean islands and the far north, and extends eastward through the Palearctic to Siberia and south-east to the Black Sea region and Iran.
Source: Wikipedia
Same family (Noctuidae)
Ipsilon Dart MothAgrotis ipsilonDamages trees, gardens or crops
Fall Armyworm MothSpodoptera frugiperdaDamages trees, gardens or crops
Army Cutworm MothEuxoa auxiliarisDamages trees, gardens or crops
Large Yellow UnderwingNoctua pronubaDamages trees, gardens or crops
Silver ΥAutographa gamma
American DaggerAcronicta americanaCan irritate skinSources
- Wikipedia: https://en.wikipedia.org/wiki/Double_square-spot
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.