This osteolepid is found in Caithness below the Achanarras horizon and should be present in Orkney below the Sandwick Fish Bed, however, the species has never been positively identified in sediments from Orkney.
John Flett Brown has found osteolepid scales in sediments of the Lower Stromness beds near Stromness and we presume that they belong to Thursius macrolepidotus but the head is needed for identification.