Foliage accumulations of Osmunda lignitum (osmundaceae) in the Oligocene of northern Italy and western Germany

Abstract

Accumulations of Osmunda (Plenasium) lignitum (Giebel) Stur fern foliage have been recently recovered in the Oligocene deposits of northern Italy at Cassinelle and western Germany at Niederpleis-1 (Sankt Augustin; Winterscheid 2006). They morphologically match other European records distributed from the Eocene to the Oligocene (– early Miocene). Material from both sites represents sterile pinnae compressions with preserved leaf anatomy. The data obtained on leaf cuticles correspond to most of the previous findings from Germany (Geiseltal, Seifhennersdorf, Haselbach) but cast doubts on some others based on dispersed cuticles (e.g. Zülpich). Comparison with living species of Osmunda (Plenasium) from east and south-east Asia revealed only minor differences in the epidermal structure and stress the close relationship with Osmunda banksiifolia (C. Presl) Kuhn distributed along valley streams from China, Japan to Indonesia, New Guinea and Philippines.