Wang Deming, Liu Le, Meng Meicen, Xue Jinzhuang, Liu Tuo, Guo Yun
Key Laboratory of Orogenic Belts and Crustal Evolution, Department of Geology, Peking University, Beijing, 100871, China,
Naturwissenschaften. 2014 Aug;101(8):615-22. doi: 10.1007/s00114-014-1187-x. Epub 2014 Jun 26.
Seed plants with ovules were abundant in the Late Devonian of Euramerica and they contribute significantly to our understanding of their early history. However, coeval ovules have been scarce in other regions of the world. Specimens of the seed plant Cosmosperma polyloba gen. et sp. nov. Wang et al. were recently obtained from the Upper Devonian (Famennian) Wutong Formation, at Fanwan Village, Changxing County, Zhejiang Province, China. This new seed plant has cupulate ovules, the uniovulate cupules with up to 16 distal segments and with minute spines on the outer surface, synangiate pollen organs bearing six to eight microsporangia fused only at the base, and planate and highly dissected pinnules in alternate arrangement. It differs from other Devonian seed plants mainly in the organization and position of the uniovulate and ornamented cupule, and in the highly dissected pinnules. Cosmosperma Wang et al. represents the first Devonian ovules recovered from China or eastern Asia and further illustrates the diversity of early spermatophytes. As for the Late Devonian seed plants, it is suggested that the pollen organs are synangiate and simple in organization, and the branches and leaves are generally planate.
在欧美地区的晚泥盆世,具胚珠的种子植物十分丰富,它们对我们了解其早期历史有着重要贡献。然而,在世界其他地区,同一时期的胚珠却很稀少。种子植物多叶宇宙籽(Cosmosperma polyloba)的标本是最近在中国浙江省长兴县范湾村上泥盆统(法门阶)五通组获得的。这种新的种子植物具有杯状胚珠,单胚珠杯状体有多达16个远端裂片,外表面有微小的刺,聚合囊状花粉器官有6至8个小孢子囊,仅在基部融合,小羽片扁平且高度深裂,呈互生排列。它与其他泥盆纪种子植物的主要区别在于单胚珠且具纹饰的杯状体的结构和位置,以及高度深裂的小羽片。宇宙籽属(Cosmosperma)Wang等人代表了首次从中国或东亚发现的泥盆纪胚珠,进一步说明了早期种子植物的多样性。至于晚泥盆世的种子植物,有人认为其花粉器官为聚合囊状且结构简单,枝叶通常扁平。