A new Cephalotaxus and associated epiphyllous fungi from the Oligocene of Guangxi, South China

Cephalotaxus ningmingensis sp. nov. is described from the Oligocene Ningming Formation of Guangxi, South China on the basis of leafy shoots and detached leaves with well preserved cuticle. This is the first fossil record of Cephalotaxus in the low latitude tropical area. The new species has been compared with living and other fossil species hitherto described of the genus. It is most similar to the living Cephalotaxus oliveri Masters and Cephalotaxus bonseri (Knowlton) Chaney et Axelrod from the Miocene of Spokane, North America in leaf gross morphology and epidermal characters. A cladistic analysis based on epidermal characters is made for all described fossil species of the genus Cephalotaxus, with Thomasiocladus zamioides Florin, which is believed to be the earliest reliable fossil of Cephalotaxaceae, as an out-group. The analysis shows that fossil species of Cephalotaxus may be divided into three phylogenetic groups and the group containing C. ningmingensis is basal in the genus. The presence of the epiphyllous fungus Callimothallus pertusus Dilcher on leaves of C. ningmingensis likely indicates a humid climate during the Oligocene in Guangxi.