Format: ORAL

Chong Dong 1,*, Gongle Shi 1, Fabiany Herrera 2, Yongdong Wang 1, Patrick S. Herendeen 3 and Peter R. Crane 4, 5

1 Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing , China 2 Field Museum of Natural History, Chicago, USA; 3 Chicago Botanic Garden, Glencoe, USA; 4 Oak Spring Garden Foundation, Upperville, USA; 5 Yale University, New Haven, USA

Taxaceae (the yew family) are a small family of conifers comprising about 25 extant species in five genera, including Taxus, Amentotaxus, Torreya, Pseudotaxus, and Austrotaxus. Their axillary ovulate structures are characterized by bearing a single terminal seed with a fleshy aril, which makes the family very different from other extant conifers. Taxaceae have a long fossil history with the earliest occurrences from the earliest Jurassic (Hettangian, 201197 Ma) of southern Sweden. Recently, we discovered well-preserved, diverse Taxaceae fossils from the Middle- Late Jurassic Daohugou Biota (~165-158 Ma) in eastern Inner Mongolia, northeastern China. These include a least four species that could be assigned to Amentotaxus, Taxus, Torreya and probably an extinct genus different from all extant genera of Taxaceae. Among the new fossils, Amentotaxus ningchengensis sp. nov. and Taxus daohugouensis sp. nov. are based on leafy shoots with attached seed-bearing structures, and they resemble those of extant Amentotaxus and Taxus respectively in vegetative as well as ovulate features. Torreya daohugouensis sp. nov. is based on leafy shoots with well-preserved cuticles. It is also comparable to extant Torreya in morphology of leaves as well as detailed cuticle structures. The new fossils from the Dahugou Biota show that the yew family had been diverse in Northeastern China since the Middle-Late Jurassic and this pattern of diversification is also seen in early Cretaceous floras of Mongolia. Amentotaxus, Taxus and probably Torreya appeared early in the evolutionary history of the family. The Asian fossils also indicate that Amentotaxus and Taxus may have undergone little morphological change since the Middle-Late Jurassic.