BUDVARICARPUS SERIALIS KNOBLOCH & MAI, AN UNUSUAL NEW MEMBER OF THE NORMAPOLLES COMPLEX FROM THE LATE CRETACEOUS OF THE CZECH REPUBLIC

The fossil fruiting structure Budvaricarpus serialis from the Late Cretaceous (Late Turonian-Santonian) of the South Bohemian Basins, originally described as tricarpellate fruit with three to four locules in a series, is here reinterpreted as a partial inflorescences (dichasium) with three to four flowers enclosed in a common bract and is recognized as a new member of the Normapolles complex. The flowers of the Budvaricarpus dichasium typically comprise a bisexual median flower and two unisexual pistillate, lateral flowers. All flowers have an inferior ovary and four tepals in two opposite pairs. The median flower has six stamens. The ovary is bicarpellate, bilocular below, and unilocular above. There is apparently a single ovule per carpel, but only one ovule of the ovary matures into a seed, and fruits are unilocular, one-seeded nuts. Pollen grains adhering to the apical part of fruits are of the Plicapollis type, a characteristic member of the Normapolles group. Individual flowers/fruits of Budvaricarpus are closely similar to those of the extinct Normapolles genus Caryanthus, which also has associated Plicapollis-type pollen. The general floral organization of Budvaricarpus is also similar to that of extant Rhoiptelea chiliantha (Rhoipteleaceae), and the associated Plicapollis pollen closely resembles pollen of Rhoiptelea.