Latest Frasnian trilobites are recorded for the first time from North Africa. They occur in oxygenated limestones between the Lower and Upper Kellwasser horizons at Bou Ounabdou near Mrirt, central Moroccan Meseta. The faunas are very close to the contemporaneous associations in European sections both by their taxonomic composition and by patterns of evolutionary behavior towards eye reduction. Two new taxa are described: Gondwanaspis mrirtensis gen. et sp. nov., which is the last known representative of the Odontopleuridae before its extinction at the base of the Upper Kellwasser horizon, and Pteroparia ziegleri maroccanica subsp. nov., a geographical variant of the nominal subspecies from Sessacker in the Rhenish Slate Mountains.

Key words: Trilobita, Frasnian, Morocco, Kellwasser crisis, biogeography.

Raimund Feist [rfeist@isem.univ−montp2.fr],Institut des Sciences de l’Evolution,Université Montpellier 2, 34095 Montpellier, France.