Further study of Late Devonian seed plant Cosmosperma polyloba: its   reconstruction and evolutionary significance

doi:10.1186/s12862-017-0992-1

CORC > 北京大学 > 地球与空间科学学院

	Further study of Late Devonian seed plant Cosmosperma polyloba: its reconstruction and evolutionary significance
	Liu, Le ; Wang, Deming ; Meng, Meicen ; Xue, Jinzhuang
刊名	BMC EVOLUTIONARY BIOLOGY
	2017
关键词	Cosmosperma polyloba Frond Ovule Pollen organ Seed plant Late Devonian Wutong Formation South China SP-NOV. ZHEJIANG PROVINCE SOUTH CHINA GEN. PTERIDOSPERM CHANGXINGIA AFFINITIES IRELAND ORGAN FERNS
DOI	10.1186/s12862-017-0992-1
英文摘要	Background: The earliest seed plants in the Late Devonian (Famennian) are abundant and well known. However, most of them lack information regarding the frond system and reconstruction. Cosmosperma polyloba represents the first Devonian ovule in China and East Asia, and its cupules, isolated synangiate pollen organs and pinnules have been studied in the preceding years. Results: New fossils of Cosmosperma were obtained from the type locality, i.e. the Leigutai Member of the Wutong Formation in Fanwan Village, Changxing County, Zhejiang Province, South China. The collection illustrates stems and fronds extensively covered in prickles, as well as fertile portions including uniovulate cupules and anisotomous branches bearing synangiate pollen organs. The stems are unbranched and bear fronds helically. Fronds are dimorphic, displaying bifurcate and trifurcate types, with the latter possibly connected to fertile rachises terminated by pollen organs. Tertiary and quaternary rachises possessing pinnules are arranged alternately (pinnately). The cupule is uniovulate and the ovule has four linear integumentary lobes fused in basal 1/3. The striations on the stems and rachises may indicate a Sparganum-type cortex. Conclusions: Cosmosperma further demonstrates diversification of frond branching patterns in the earliest seed plants. The less-fused cupule and integument of this plant are considered primitive among Devonian spermatophytes with uniovulate cupules. We tentatively reconstructed Cosmosperma with an upright, semi-self-supporting habit, and the prickles along stems and frond rachises were interpreted as characteristics facilitating supporting rather than defensive structures.; China Postdoctoral Science Foundation [2016 M600146]; National Natural Science Foundation of China [41672007]; SCI(E); ARTICLE; 17
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/472653]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Liu, Le,Wang, Deming,Meng, Meicen,et al. Further study of Late Devonian seed plant Cosmosperma polyloba: its reconstruction and evolutionary significance[J]. BMC EVOLUTIONARY BIOLOGY,2017.
APA	Liu, Le,Wang, Deming,Meng, Meicen,&Xue, Jinzhuang.(2017).Further study of Late Devonian seed plant Cosmosperma polyloba: its reconstruction and evolutionary significance.BMC EVOLUTIONARY BIOLOGY.
MLA	Liu, Le,et al."Further study of Late Devonian seed plant Cosmosperma polyloba: its reconstruction and evolutionary significance".BMC EVOLUTIONARY BIOLOGY (2017).