title: A perfect flower from the Jurassic of China.
abstract: Flower, enclosed ovule and tetrasporangiate anther are three major characters distinguishing angiosperms from other seed plants. Morphologically, typical flowers are characterised by an organisation with gynoecium and androecium surrounded by corolla and calyx. Theoretically, flowers are derived from their counterparts in ancient ancestral gymnosperms. However, as for when, how and from which groups, there is no consensus among botanists yet. Although angiosperm-like pollen and angiosperms have been claimed in the Triassic and Jurassic, typical flowers with the aforesaid three key characters are still missing in the pre-Cretaceous age, making many interpretations of flower evolution tentative. Thus searching for flower in the pre-Cretaceous has been a tantalising task for palaeobotanists for a long time. Here, we report a typical flower,Euanthus paniigen. et sp. nov., from the Middle-Late Jurassic of Liaoning, China.Euanthushas sepals, petals, androecium with tetrasporangiate dithecate anthers and gynoecium with enclosed ovules, organised just like in perfect flowers of extant angiosperms. The discovery ofEuanthusimplies that typical angiosperm flowers have already been in place in the Jurassic, and provides a new insight unavailable otherwise for the evolution of flowers.
authors.affiliation: Shenzhen Key Laboratory for Orchid Conservation and Utilization, National Orchid Conservation Center of China and Orchid Conservation and Research Center of Shenzhen , Shenzhen 518114 , P.R. China.
authors.forename: Zhong-Jian
authors.initials: ZJ
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Nanjing210008, P.R. China; Palaeontological Center, Bohai University, Jinzhou121013, P.R. China.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
keywords: China; Jurassic; Liaoning; angiosperm; flower