About Papestra biren Goeze, 1781
Technical description and variation: The wingspan of Papestra biren is 30โ38 mm. Its forewing is purplish grey, suffused with blackish colouring. The stigmata are pale grey, with whitish rims edged in black. The submarginal line is whitish, and is preceded by black dentate marks. The hindwing is dark brownish fuscous. The paler or bluish-grey tint is most developed in the type form. lappo Dup. is a more ashy grey form with pale stigmata, found in Lapland, Finland, and northern Ireland. aperta Geyer represents an exceptionally dark form. taunensis Fuchs, from the Taunus Mountains, is uniform dark ruddy grey, with only the external margins of the claviform and reniform stigmata pale.
