Miocene Smilax leaves and associated epiphyllous fungi from Zhejiang, East China and their paleoecological implications

Smilax tiantaiensis sp. nov. is described from the Late Miocene Shenxian Formation in Zhejiang Province, East China based on five fossil leaves with fine venation and well preserved cuticles. The fossil leaves are characterized by an ovate shape, entire margin, mucronate apex, rounded base, five primary basal acrodromous veins with reticulate venation in between; leaves hypostomatic, anticlinal walls undulated and stomatal apparatus anomocytic. The fossils have been compared with extant and other fossil species hitherto described in this genus. Some fossil stromata, hyphae and spores identified as Callimothallus pertusus Dilcher (Microthyriaceae) were discovered on the both epidermides of S. tiantaiensis. The climbing habit of Smilax and the presence of the epiphyllous fungus of C. pertusus on the fossil leaves may indicate that the multistratified forest was growing under a humid climate during the Miocene in Zhejiang.

Research Highlights
► Leaf architectures and cuticle structures of Miocene Smilax leaves were investigated.
► Cuticle characters are helpful to fossil identifications.
► Fossil Smilax existed in the forest demonstrates a multilayered structure.
► Living habits and associated epiphyllous fungi indicate a warm and humid climate.