Keraocarpon gen. nov., magnolialean fruits from the Upper Cretaceous of Hokkaido, Japan

Two new permineralized magnolialean fruits derived from the Coniacian-Santonian strata of the Upper Yezo Group are described in this paper. Each fruit consists of floral head, convex receptacle and woody peduncle. Floral head consists of many conduplicate follicles with adaxial opening. Follicle is long stalked, unilocular and many seeded. Since the fruits differ from the already known ones of Magnoliales, a new genus Keraocarpon is proposed to include two new species, K. yasujii and K. masatoshii. A brief comparison of Keraocarpon to other magnolialean taxa is made. These two new species are distinguished from each other by the differences in size of various elements, number of follicles in the aggregate fruits, number of seeds per follicle, and other minor characters. The genus is characterized by aggregate fruits of many-seeded apocarpous stalked follicles on a slightly convex receptacle.