Fossil flora of Middle Jurassic Grojec clays (southern Poland). Raciborski’s original material reinvestigated and supplemented. II. Pteridophyta. Osmundales

Abstract

Abstract In the second part of the series dealing with the flora of the Grojec clays (Poland, Middle Jurassic), macroremains of Osmundales are introduced. The re-examined and supplemented material originates from three collections: specimens collected and described in Polish by Raciborski in 1894; specimens preliminarily described by Stur (1888), housed at the Geological Survey of Austria; and Raciborski’s still-unpublished material stored at the Institute of Botany of the Jagiellonian University. So far, 15 taxa of Cladophlebis have been described from the Osmundales of Grojec clays, and two species of Todites (Todea) and Osmundopsis (Osmunda) sturii. Detailed observations indicate that a large part of the material (12 taxa described by Raciborski) should be assigned to three widespread Jurassic species: Cladophlebis denticulata, C. haiburnensis, and C. roessertii. Cladophlebis aurita and C. bartonecii, created by Raciborski, should be retained. The occurrence of sterile and fertile fronds of Todites williamsonii (originally described as Todea williamsonis, Cladophlebis whitbiensis, and Cladophlebis solida) is confirmed for Grojec. Two species described by Raciborski (1894) required a change of generic names - Osmundopsis (Osmunda) sturii and Todites (Todea) princeps. This paper provides the taxonomical descriptions and considers the palaeoecology of 5 Cladophlebis species (C. aurita, C. denticulata, C. haiburnensis, C. roessertii, C. bartonecii) and other osmundaceous ferns such as Osmundopsis sturii, Todites williamsonii, and T. princeps.