Lauraceous Inflorescences and Flowers from the Cenomanian of Bohemia (Czech Republic, Central Europe)

Abstract

A new species of the fossil genus Mauldinia Drinnan et al. (Lauraceae) is described from the Cenomanian of Bohemia, Czech Republic, central Europe. This constitutes the first well-documented report of Lauraceae from the European Cretaceous, and a new species, M. bohemica, is based on a large assemblage of compression fossils as well as three-dimensionally preserved specimens. Inflorescences are of the same unique organization as in the type species, with distinctly bilobed lateral inflorescence units attached on elongated central axes in a helical arrangement Lateral inflorescence units are dorsiventrally flattened and composed of small leaflike scales that are closely attached in a distichous arrangement on each lobe. Flowers are borne in the axils of the leaflike scales on the adaxial surface of each lobe. Flowers are trimerous with two perianth whorls, nine fertile and bivalvate stamens in three whorls, three staminodes in an inner fourth whorl, and a single carpel. A pair of staminal appendages with glandular heads is associated with the filaments of the third staminal whorl. A hypothesis concerning the derivation of the peculiar Mauldinia inflorescence is discussed and includes reduction and condensation of proliferating dichasia through a process called "syndesmy." A survey of the fossil record showed that Mauldinia had a wide geographic distribution and was an important element in many floras during the Cenomanian.