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The Cornales are an order of flowering plants, basal among the asterids, containing about 600 species. Plants within the Cornales usually have four-parted flowers, drupaceous fruits, and inferior gynoecia topped with disc-shaped nectaries. Under the APG system, the Cornales order includes these families: * Cornaceae (the dogwood family, including Nyssaceae, the tupelos) * Curtisiaceae (cape lancewood) * Grubbiaceae (the sillyberry family) * Hydrangeaceae (the hydrangea family) * Hydrostachyaceae * Loasaceae (the stickleaf family) ==Phylogeny== The Cornales urder is sister to the remainder of the large and diverse asterid clade. The Cornales are highly geographically disjunct and morphologically diverse, which has led to considerable confusion regarding the proper circumscription of the groups within the order and the relationships between them.〔Xiang, Q. Y., Soltis, D. E., Morgan, D. R., and Soltis, P. S. (1993). Phylogenetic relationships of ''Cornus'' L ''sensu lato'' and putative relatives inferred from rbcL sequence data. ''Annals of the Missouri Botanical Garden'' 80, 723-734.〕 Under the Cronquist system, the order comprised the families Cornaceae, Nyssaceae, Garryaceae, and Alangiaceae, and was placed among the Rosidae, but this interpretation is no longer followed. Many families and genera previously associated with the Cornales have been removed, including Garryaceae, ''Griselinia'', ''Corokia'', and ''Kaliphora'', among others.〔 Molecular data suggest four clades are within the Cornales: ''Cornus-Alangium'', nyssoids-mastixioids, Hydrangeaceae-Loasaceae, and ''Grubbia-Curtisia'', with the Hydrostachyaceae in an uncertain position, possibly basal.〔Fan, C. Z., and Xiang, Q. Y. (2003). Phylogenetic analyses of Cornales based on 26S rRNA and combined 26S rDNA-matK-rbcL sequence data. ''American Journal of Botany'' 90, 1357-1372.〕 However, the relationship between these clades is unclear, and as a result of many historical taxonomic interpretations and differing opinions regarding the significance of morphological variations, rankings of taxa within the order are inconsistent.〔〔〔Eyde, R. H. (1988). Comprehending ''Cornus'' - puzzles and progress in the systematics of the dogwoods. ''Botanical Review'' 54, 233-351.〕 These difficulties in interpreting the systematics of Cornales may represent an early and rapid diversification of the groups within the order.〔 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「Cornales」の詳細全文を読む スポンサード リンク
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