Seq # 900310070

Acronicta psi (Linnaeus, 1758) Species

Last modified: June 18, 2022, 4:11 p.m.

A fairly common species throughout Belgium.


Family: Noctuidae > Subfamily: Acronictinae > Genus: Acronicta > Subgenus: Triaena > Species: Acronicta psi
Vernacular names
Psi-uil (NL), Grey Dagger (EN), Le Psi (FR), Pfeileule (DE)
First mention in Belgium
De Sélys-Longchamps E. 1844. Énumération des insectes Lépidoptères de la Belgique. — Mémoires de la Société royale des Sciences de Liége 2: 1–35. On page 10.




Wingspan: 30–40 mm.
Adults of Acronicta cuspis, Acronicta tridens and Acronicta psi cannot be safely distinguished from each other, except by reference of the genitalia. Allthough larvae of these species are quiet different and are easy to identify as species.

Museum specimens

Specimens in nature



Can be found from May till November.


Hibernates as a pupa in a loose grey cocoon under loose bark, in a crevice or in decayed wood.
The adults come to light and sugar.

No pictures yet!

Flight periods

The adults fly in two generations a year from mid April towards mid September.

Observed on

Host plant (species):
Prunus spinosa
Host plant (genera):
Crataegus, Malus, Betula, Tilia, Ulmus and Sorbus
Deciduous trees and Shrubs

The larva lives on a wide range of broadleaved trees and shrubs, including: Prunus spinosa, Crataegus, Malus, Betula, Tilia, Ulmus, Sorbus etc...

No pictures yet!