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Velloziaceae is a family of monocotyledonous flowering plants. The APG II system, of 2003 (unchanged from the APG system, 1998), also recognizes this family, and assigns it to the order Pandanales. ==Relationships and Evolution== By contrast to other members of Pandanales the family demonstrates stricter flower morphology. Despite that, the flower structure is still quite variable and with a lot of specifics. Thus morphological analyses are not able to uncover realistic phylogenetical relationships neither appropriate taxonomy. Embryological development places the family among the amaryllids while the composition of the ovary puts it near the distinct Hypoxidaceae. However, a study regarding the pollen structure in two genera from Velloziaceae was found to be an important character and suggests some correlation but this is still a variable trait. Molecular analyses〔http://aob.oxfordjournals.org/content/108/1/87.abstract〕 recognize five distinct genera (by including ''Talbotia'' in ''Xerophyta'' and ''Nanuza'' in ''Vellozia'' thus forming two sister groups) and show that the monotypic genus ''Acanthochlamys'' is sister to the rest of the members. The family originated in Gondwana. The crown group is dated to be very young - 14 Mya (Mid Neogene) but the stem group was found to be much older - 108 Mya (Mid Cretaceous).〔http://www.senckenberg.de/files/content/forschung/abteilung/botanik/phanerogamen1/janssen_janssenbremer_2004_monocotages.pdf〕 }} }} }} }} 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Velloziaceae」の詳細全文を読む スポンサード リンク
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