A Lower Ordovician (Arenig) radiolarian fauna from the Ballantrae Complex, Scotland

Abstract

Recent examinations of Lower Ordovician (Arenig) cherts from the Ballantrae Complex, Scotland have resulted in the discovery of a moderately well-preserved radiolarian assemblage. Elements of the fauna are distinctive indicating that even early radiolarian forms have excellent biostratigraphic potential. The abundance of radiolarians in chert and the ease with which they can be extracted suggest that they are a potentially valuable tool for use in investigations into the timing of the development of Early Palaeozoic orogenic systems. A new family of Radiolaria the Proventocitiidae fam. nov., previously informally described from Spitsbergen (Fortey and Holdsworth 1971), is formalized herein. One new species, Proventocitum holdsworthi, sp.nov., is described; Proventocitum sp.A is described under open nomenclature.