J Syst Evol ›› 2013, Vol. 51 ›› Issue (6): 758-764.DOI: 10.1111/jse.12030

• Research Articles • Previous Articles     Next Articles

The first fossil Microsoroid fern (Palaeosorum ellipticum gen. et sp. nov.) from the middle Miocene of Yunnan, SW China

1Frédéric M. B. JACQUES 1Tao SU 1,2Zhe-Kun ZHOU*   

  1. 1(Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, China)
    2(Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China)
  • Received:2013-03-06 Published:2013-07-10

Abstract: The microsoroid ferns make up a large group in the family Polypodiaceae, easily characterized by the combination of at least partly clathrate rhizome scales and anastomosing reticulate venation. The diversification of this clade is poorly known, both because of unresolved generic delimitations and the lack of fossil records. In this work, we describe the first microsoroid macrofossil: Palaeosorum ellipticum sp. nov. F. M. B. Jacques & Z. K. Zhou. The fossil specimen, represented by part and counterpart, was found in the middle Miocene sediment of the Dajie Formation in Ailsohan, central Yunnan, southwest China. Epiphytic ferns belonging to Drynariaare found in different locations in Yunnan during the Pliocene. The fossil described in this study deepens the occurrence of epiphytic ferns in Yunnan back to the middle Miocene. It demonstrates that forests with complex ecological relationships have existed in southwest China for more than 10 million years.

Key words: epiphytism, fossil, Palaeosorum, Miocene, Polypodiaceae, Yunnan.