Early Devonian spore assemblages from the Dingle Group, County Kerry, Ireland

The Dingle Group is the lowest lithostratigraphic division of the continental Old Red Sandstone magnafacies in the Dingle Peninsula of southwest Ireland. It is generally considered to be Late Silurian (Ludlow) to Early Devonian in age, but to data has yielded no unequivocal faunal or floral evidence of age. This paper describes two small but distinctive Early Devonian spore assemblages from the Dingle Group in the southwestern part of the Dingle Peninsula. The older assemblage is from the Eask Formation at Dunmore Head and is assigned to the D. wetteldorfensis (W) Interval Zone of early late Pragian age. The younger assemblage is from the Slea Head Formation and is assigned to the E. annulatus-B. bellatulus (AB) Oppel Zone of early to middle(?) Emsian age. The stratigraphic significance of these newly inferred early Devonian datings is discussed, particularly with reference to the contact with the underlying Silurian Dunquin Group. The palynological evidence now shows that the bulk of the Dingle Group belongs to the Early Devonian and the most likely position for the Silurian-Devonian boundary is within the basal Bulls Head Formation.