Zlivifructus gen. nov., a new member of the Normapolles complex

Abstract

New Normapolles reproductive structures are described from several Late Cretaceous stratigraphic horizons of central and western Europe: the Klikov Formation (late Turonian–Santonian), the Aachen Formation (Santonian) and the Walbeck Formation (Maastrichtian). They are assigned to a new genus, Zlivifructus, containing three new species, Zlivifructus vachae, Zlivifructus sklenarii and Zlivifructus sp. The new genus is based on several small flowers/fruits. The flowers are bisexual, bisymmetrical and have an inferior ovary with a hypanthium. The tepals are attached on top of the hypanthium. The genus has four tepals, in two decussate pairs. The androecium consists of four stamens. The gynoecium is bicarpellate, with a unilocular ovary and two styles. Fruits are nuts with a single erect, orthotropous seed. Zlivifructus is separated from Caryanthus based on the presence of four stamens. Both bear pollen grains of the Normapolles group. Organization of the flowers/fruits in Zlivifructus, as well as the structure of the pollen indicate that this new Normapolles flower is of core fagalean affinity. The new genus is closely related to other Normapolles genera, particularly Caryanthus, and may be close to the base of the Juglandaceae-Rhoipteleaceae clade.