Somnium
Cyphaspis cf. heissae
VAN VIERSEN & PRESCHER, 2014
Middle Devonian, upper Eifelian, Hanonet Formation (lower part)
"Devil horned" Cyphaspis (Trilobita, Otarioninae): examples from the Middle Devonian of the Ardennes (Belgium), Eifel (Germany) and Ma'der (Morocco).
Geologica Belgica (2014) 17/3-4: 268-275