I. Mannerkoski & J. Ferrer 1992: Cynaeus opacus Champion, a New Tenebrionid Beetle in Finland (Coleoptera, Tenebrionidae). - Entomologica Fennica 3: 95-97.
From 1989 on Cynaeus opacus Champion has been found in waste heaps and similar localities in southern Finland together with other synanthropic beetles. Cynaeus is an American genus spreading with man; another species, C. angustus (LeConte), has recently been recorded from Sweden.