| 摘要 | 经对中国伞形科天胡荽亚科( Hydrocotyloideae) 中天胡荽属( Hydrocotyle L.) 积雪草属( Centella L.) 和马蹄芹属
( Dickinsia Franch.) 10 种植物果实解剖结构的观察比较, 发现 3 属的果实横切面以合生面为基准可以分成 2 个类型,
即两侧压扁类型( 天胡荽属和积雪草属) 和背腹压扁类型( 马蹄芹属) 。 除此之外, 中果皮的外侧是否有色素块沉
积、内侧是否有木化细胞层或厚壁细胞层以及最内层是否形成晶体细胞层, 内果皮细胞的层数、排列方向以及有无
棱槽油管等性状, 可以作为区分 3 属的重要解剖学特征。 在此基础上, 结合外部形态特征, 讨论了该亚科及其内部
各属的解剖学特征、属间区别及其演化关系。 认为马蹄芹属应归属于 Mulineae 族, 另外 2 个属应归属于天胡荽族
( Hydrocotyleae) ;3 属中积雪草属原始而马蹄芹属进化;天胡荽亚科可能不是自然的类群, 它的分类系统和演化地位
有待深入研究。
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| Abstract | The comparative anatomical structure of fruits from 10 species of 3 genera ( Hydrocotyle L .,
Centella L .and Dickinsia Franch .) in Hydrocotyloideae of Apiaceae distributed in China is observed .In median transection their mericarp are divided into 2 types based on the commissure, one flattened latrally ( Hydrocotyle and Centella ) and another flattened dorsally ( Dickinsia ) .In addition, other important distinctions of the mericarp anatomy in three genera are as follows :whether or not to have pigment granule, crystal cell layer, lignified cell layer and thicken wall cell layer in mesocarp ;arranging direction of the cells and cell layers in endocarp ;as well as whether to have oil tube in rib vallecula or not .On the bases of above anatomical characters the evolutionary relationship among them are discussed combining with the external morphological characters. Dickinsia belongs to the tribe Mulineae and other two genera the tribe Hydrocotyleae.The evolutionary level of Centella is the lowest and Dickinsia the highest in 3 genera.Hydrocotyloideae may be not a natural taxon just as the conclusion from DNA molecular information .
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