Plant Diversity ›› 2022, Vol. 44 ›› Issue (06): 565-576.DOI: 10.1016/j.pld.2021.09.003

• Research paper • Previous Articles     Next Articles

Fertile Woodwardia from the middle Eocene of South China and its implications for palaeogeography and palaeoclimate

Han-Zhang Songa, Serge V. Naugolnykhb,c, Xin-Kai Wud, Xiao-Yan Liue, Jian-Hua Jina   

  1. a. State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China;
    b. Geological Institute of Russian Academy of Sciences, Moscow, 119017, Russia;
    c. Contract Affiliation:Kazan Federal University, Republic of Tatarstan, Russia;
    d. School of Ecology, Sun Yat-sen University, Guangzhou 510275, China;
    e. School of Geography, South China Normal University, Guangzhou 510631, China
  • Received:2021-06-03 Revised:2021-09-03 Online:2022-11-25 Published:2022-12-13
  • Contact: Xiao-Yan Liu,E-mail:lxy_0628@163.com;Jian-Hua Jin,E-mail:lssjjh@mail.sysu.edu.cn
  • Supported by:
    This study was supported by the National Natural Science Foundation of China (Grant Nos. 41872015, 42111530024, 41820104002, 41661134049 to JHJ and XYL), a grant from the UK Natural Environment Research Council (Grant No. NE/P013805/1 to XYL), the Fundamental Research Funds for the Central Universities (Grant No. 2021qntd18 to XKW), the Scientific Research Fund, Hongda Zhang, Sun Yat-sen University, and a subsidiary of the Russian Government that supports a Program of Competitive Growth of Kazan Federal University among World's Leading Academic Centers and the State Program of Geological Institute of RAS (Grant No. 0135-2019-0044 to SVN).

Abstract: The genus Woodwardia, which together with the genera Anchistea and Lorinseria comprise the subfamily Woodwardioideae of Blechnaceae, has a disjunct distribution across Central and North America, Europe and the temperate to tropical areas of Asia. Fossil records of Woodwardia occur throughout the Paleogene and Neogene of North America, Europe and Asia. However, well-preserved fertile pinna fossils of this genus have not yet been reported in South China. In this paper, a new species, W.?changchangensis Naugolnykh et Song, sp. nov. is described from the middle Eocene of the Changchang Basin, Hainan Island, South China. Macromorphological and micromorphological features of the fertile pinna show a straight pinna rachis, alternate, subtriangular pinnules, acute pinnule apices, almost entire or slightly undulate pinnule margins, long-ovoid sori, stalked sporangia and spores with wing-like folds on the surface, which are characterised in detail. Overall, the present fossil is most similar to the extant species Woodwardia japonica, which mostly grows in warm and moist environments. The discovery of this new species from the Changchang Basin of Hainan Island indicates that this genus has been distributed in the low-latitude tropical regions of South China from as early as the middle Eocene. Based on this find, and previous studies of other ferns from the same site, we infer that the climate of the Palaeo-Hainan landscape during deposition of the Changchang Formation was warm and humid, similar to conditions prevailing today across this region.

Key words: Woodwardia, Eocene, Climate, Hainan Island, South China