A new Oligocene species of Cunninghamia R. Brown ex Richard et A. Richard (Cupressaceae) from the Maoming Basin, South China

Abstract

A new species of the genus Cunninghamia (Cupressaceae s.l.) is reported from the Lower Oligocene Shangcun Formation of the Maoming Basin, Guangdong Province, South China based on compressions/impressions of leafy shoots and an isolated leaf. Cunninghamia shangcunica sp. nov. possesses helically arranged and radially spread polymorphic leaves. Most Cretaceous cunninghamioid species exhibits a similar phyllotaxis with this new species, and it can be regarded as a primitive character. In the Miocene species, terminal shoots with a bilateral (pectinate) arrangement of leaves predominated. The new species is similar to the extant species C. konishii in shoot and leaf morphology, and to С. lanceolata in the characters of the epidermis. The new Oligocene species increases the known diversity of the genus Cunninghamia in its refugial region and contributes to a greater understanding of the specific variability and ecology of this conifer. A diverse population of epiphyllous fungi on the leaves of the new species are recorded and figured.