【摘 要】
:
具有孢子叶球的石松类始现于中泥盆世吉维特期,繁盛于晚泥盆世法门期,但其弗拉期化石记录较为缺乏.基于湖南长沙附近弗拉阶云麓宫组的材料,本文描述了三种石松类孢子叶球未定
【机 构】
:
中国矿业大学(北京),地球科学与测绘工程学院,北京100083;北京大学地球与空间科学学院,造山带与地壳演化教育部重点实验室,北京100871
论文部分内容阅读
具有孢子叶球的石松类始现于中泥盆世吉维特期,繁盛于晚泥盆世法门期,但其弗拉期化石记录较为缺乏.基于湖南长沙附近弗拉阶云麓宫组的材料,本文描述了三种石松类孢子叶球未定类型.其中一类孢子叶球具有独特的孢子叶形态和排列方式:其孢子叶呈交互假轮生排列,每轮四枚;叶片呈斜方形,顶端具线形叶尖.另两种石松类叶球未定类型分别以无柄的孢子叶和二分叉的叶球为特征.本文复原了第一类叶球的三维形态,就压型保存的石松类孢子叶球化石的埋藏学进行了讨论,并将所研究的三种石松类孢子叶球与相关植物进行对比,增进了对弗拉期石松类繁殖器官多样性的认识.“,”Lycopsid with strobili first occurred in the Givetian and were abundant in the Famennian of the Devonian,while their fossil record in the Frasnian is insufficient.Based on specimens from the Frasnian Yunlugong Formation at a location near Changsha City,Hunan Province,China,we describe three undetermined lycopsid strobili showing divergent morphologies despite the limited material.One type of these strobili displays unique morphological traits,including the slender strobili bearing sporophylls in alternate pseudowhorls of four,and the sporophylls with linear distal tips and rhombic laminae.The other two types of undetermined strobili are characterized by sessile sporophylls and bifurcate strobilar axes,respectively.The first type mentioned above is reconstructed and discussed within a taphonomic context of compression fossils of strobili.The present materials are compared with related taxa,and add to the diversity of the reproductive organs of Frasnian lycopsids.
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