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bioRxiv · 10.1101/240226

Nanjinganthus:An Unexpected Flower from the Jurassic of China

Abstract

The origin of angiosperms has been the focus of intensive botanical debate for well over a century. The great diversity of angiosperms in the Early Cretaceous makes the Jurassic rather expected to elucidate the origin of angiosperm. Former reports of early angiosperms are frequently based on a single specimen, making many conclusions tentative. Here, based on observations of 284 individual flowers preserved on 28 slabs in various states and orientations, we describe a fossil flower, Nanjinganthus dendrostyla gen. et sp. nov., from the South Xiangshan Formation (Early Jurassic) of China. The large number of specimens and various preservations allows us to give an evidenced interpretation of the flower. The complete enclosure of ovules in Nanjinganthus is fulfilled by a combination of an invaginated and ovarian roof. Characterized by its actinomorphic flower with a dendroid style, cup-form receptacle, and angio-ovuly, Nanjinganthus is a bona fide angiosperm from the Jurassic. Nanjinganthus re-confirms the existence of Jurassic angiosperms and provides first-hand raw data for new analyses on the origin and history of angiosperms.

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BibTeXRIS

fu, q., DIEZ, J. B., POLE, M., GARCIA-AVILA, M., LIU, Z.-J., CHU, H., Hou, Y., YIN, P., ZHANG, G.-Q., DU, K., WANG, X.. 2017-12-27. Nanjinganthus:An Unexpected Flower from the Jurassic of China. https://doi.org/10.1101/240226

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