Small Purple-barred Noctuidae

Phytometra viridaria (Clerck, 1759)

Description: Wingspan 19-20 mm. A small inconspicuous species that is most active in sunshine. Forewings are a mixture of olive and purple brown. Antemedian line not visible, post median line broad ranging in colour from light to dark purple brown. Hindwings similar in colour to forewings.

Key Identification Features:

Sets:  male upperside

Flight Period: Mid-April to mid-June.

Status: Widely distributed but local; recorded from all counties in the past. In recent times it has been more commonly encountered in southern counties, especially in Fermanagh where it has been seen frequently in some well-recorded grassland sites such as Monawilkin. In the east it has been found on the lower slopes of the Mournes at Leitrim Lodge and Annalong Wood. It has not been recorded from Londonderry since 1972. Its resemblance to a small micro moth makes it easily overlooked by all but experienced recorders.

Ecology: A small dayflying species found in upland and lowland bogs, heaths and limestone grasslands. The adults normally fly rapidly in sunshine, usually settling on bare ground or short vegetation. They are generally wary and difficult at times to approach. The larvae feed from July to September on Common Milkwort Polygala vulgaris. It overwinters as a pupa.

World Distribution: Eurasiatic; common and widespread on heaths throughout western Europe as far north as Finland.

Bradley & Fletcher number: 2470 Agassiz number: 72.067

Additional information:

UK Moths account


 Thompson, R. S. & Nelson, B., 2003 (Oct 2). [In] The Butterflies and Moths of Northern Ireland