Papestra biren, the glaucous shears, is a moth of the family Noctuidae. The species was first described by Johann August Ephraim Goeze in 1781. It is found in most of Europe, but not in the southern parts of the Iberian Peninsula, Italy and Greece. Outside of Europe it is found in Kashmir and through the Palearctic to Siberia, Central Asia, Amur, Kamchatka, the Russian Far East and Japan. It was introduced in Newfoundland in 1935 and has since then extended its range ever more southward within North America partly overlapping with Papestra quadrata (Smith, 1891). It rises to 2200 m above sea level in the Alps.