REVIEW OF PALAEOBOTANY AND PALYNOLOGY ELS EV I ER Reviewof Palaeobotanyand Palynology 84 (1995) 389-412 Cycadales and Bennettitales leaf compressions of the Bohemian Cenomanian, Central Europe Jifi Kva~ek National Museum, Prague, Department of Palaeontology, V6clavskk n6m. 68, Prague 1, Czech Republic Received 14 February 1994; revised and accepted 5 May 1994 Abstract Three species of cycad leaves from the Bohemian Cenomanian, Central Europe, are described and revised on the basis of their cuticle: Jirusia jirusii (Bayer) J. Kva6ek, comb. nov., Nilsonia bohemica Velenovsk~, and Nilsonia cf. orientalis Heer, Additionally, the genus Jirusia Bayer, 1914 is newly reintroduced and defined. For the first time a bennettitalean leaf compression species is recorded in the Bohemian Cenomanian and described as Nilssoniopteris pecinovensis J. Kva~ek, sp. nov. 1. Introduction The main object of this paper is to describe and contribute to the knowledge of some new and previously known taxa of Cycadales and Bennettitales from the Cenomanian of Bohemia. Fossil cycads from the Cretaceous of Bohemia were first recorded by Reuss (1844) and Corda (see Reuss, 1846). Many fossil cycads were described by Velenovsk~ (1885) and Bayer (1901, 1914). While Velenovsk), who comprehensively described the whole Cenomanian flora of Bohemia, concentrated only on macroscopical descriptions, Bayer (1914, 1921) used microscopical methods and cuticle maceration. He especially collected cuticle-bearing specimens. Further studies were done by Velenovsk2) and Viniklfi~ (1926, 1927, 1929, 1931) and Vinikl~i~ (1933). Later, cycads were mentioned only in lists of occurring taxa (Knobloch, 1969, 1971, 1987). The only previously described bennettitalean representative from the Bohemian Cretaceous Basin is a silicified stem, figured by N6mejc (1968). Additionally, some leaf impressions and silicified 0034-6667/95/$9.50© 1995Elsevier Science B.V.All rights reserved SSDI 0034-6667(94)00093-Y stems are known from the Lower Cretaceous of Moravia (Hlugtik and Purkyfiovfi, 1982; Purkyfiovfi, 1983). 2. Material and methods Material for the present study has been derived from the Peruc-Korycany Formation (Cenomanian) of the Bohemian Cretaceous Basin, as defined by Cech et al. (1980). The Peruc- Korycany Formation consists of the Peruc Member, the Korycany Member and the Pecinov Member (Fig. 1). The lower part of the Peruc Member includes fluvial sands and sandstones, mudstones and interbedded mudstones, supratidal marsh and back swamp deposits crossed by mean- dering tidal creeks close to the eustuarine mouth in the area of south-central Bohemia (Uli6n~, 1992). It continually evolved into the marine Korycany Member, built by sandstones containing a rich marine fauna and occasionally preserved stems of tree ferns and poor leaf impressions. In