A new Lower Carboniferous flora from East Lothian, Scotland

Abstract

Fossil plants of probable late Courceyan age have been discovered in fluvial sandstones at Castleton Bay, near North Berwick, East Lothian, Scotland and are anatomically preserved as calcareous permineralizations. This restricted flora is dominated by Eristophyton and Lyginorachis , a probable pteridosperm and the lycopod Lepidodendron calamopsoides . Bisporangiate lycopod cones associated probably belong to this plant. The pteridosperm Stenomyelon and its petiole Kalymma also occur. Rarer elements include the ferns Cladoxylon, Protoclepsydropsis and some ovules. The flora has much in common with others from similar facies in the south of the Midland Valley Basin and in the Tweed Basin and differs markedly from the slightly younger flora from Oxroad Bay which occurs in basaltic volcanic ashes. These differences may be explained by a combination of depositional, preservational and original ecological differences rather than by age. A comparison of the floras from the Tweed Basin and the Midland Valley Basin confirms their similarity and indicates a single palaeobiogeographic province and any barrier which may have existed in the Southern Uplands did not prevent plant migration between the basins.