Fertile pinnules of Danaeites rigida Gu and Zhi (Marattiales) from the Upper Permian of south China
Fertile pinnules of Danaeites rigida Gu and Zhi (Marattiales) from the Upper Permian of south China
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DOI：
10.1111/j.1095-8339.2001.tb00559.x
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发表时间：
2001-05
影响因子：
2.4
通讯作者：
Zhaoqun Liu;Cheng-Sen Li;J. Hilton
中科院分区：
文献类型：
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作者：
Zhaoqun Liu;Cheng-Sen Li;J. Hilton
对最近采自华南晚二叠世的Danaeites rigida Gu和Zhi标本进行了详细的形态学研究，以揭示其可育羽片的特征。标本被保存为压缩/印象，并拥有pecopteroid型小羽片与一个单行的synangia两侧的小羽片midvien。单个的合囊两侧对称，无柄，其基部嵌入羽片的组织中。合囊体有18-24个孢子囊，在它们的整个长度上彼此横向融合。孢子囊通过一条纵缝裂开，孢子囊含有三裂孢子，孢子颗粒状，与分散的孢子环花岗岩孢子体相似。这种特征的组合在通过压缩/压痕保存的标本中是独特的，尽管它们与那些已知的过矿化的marattialean肥沃的叶状体相似。然而，解剖学的细节突出的这些过矿化类群的识别是无法识别的印象/压缩化石，如Danaeites。这些研究结果的分类和系统发育的影响被认为是详细的，我们得出结论，Danaeites有更密切的联系与Marattia比Danaea。
Recently collected specimens of Danaeites rigida Gu and Zhi from the Upper Permian of south China have been subjected to detailed morphological investigations in order to reveal features of their fertile pinnules. The specimens are preserved as compression/impressions and possess pecopteroid-type pinnules with a single row of synangia on either side of the pinnule midvien. Individual synangia are bilaterally symmetrical, sessile, and their bases are embedded in the tissues of the pinnules. Synangia possess 18–24 sporangia that are laterally fused to one another throughout their entire length. Sporangial dehiscence is through a longitudinal slit and sporangia contain trilete spores with a granular ornamentation, referable to the dispersed spore Cyclogranisporites. This combination of characters is unique in specimens preserved by compression/impression although they are similar to those known in permineralized marattialean fertile fronds. However, anatomical details salient to the identification of these permineralized taxa are not identifiable in impression/compression fossils such as Danaeites. The taxonomic and phylogenetic implications of these findings are considered in detail and we conclude that Danaeites has closer links with Marattia than with Danaea.