Cornales

 ( Angiosperm Orders ) 

The Cornales are an order of , early diverging among the asterids, containing about 600 species. Plants within the Cornales usually have four-parted flowers, Drupe fruits, and inferior to half-inferior gynoecia topped with disc-shaped .

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Taxonomy In the classification system of Rolf Dahlgren the Cornales were in the superorder Corniflorae (also called Cornanae). Under the APG IV system, the Cornales order includes these families:

• Cornaceae (the dogwood family)
• Curtisiaceae (cape lancewood)
• Grubbiaceae (the sillyberry family)
• Hydrangeaceae (the hydrangea family)
• Hydrostachyaceae
• Loasaceae (the Mentzelia family)
• Nyssaceae, (the tupelos)

The oldest fossils assigned with confidence to the order are Hironoia, described from Coniacian age Japanese coalified fruits, and Suciacarpa described from American permineralized fruits of Campanian age.

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Phylogeny The Cornales order 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.

Likely cladogram for Cornales:Based on Figure 11.10 in

(2025). 9780226383613, University of Chicago Press. ISBN 9780226383613

Molecular data suggest four clades are within the Cornales: Cornus-Alangium, Nyssaceae, Hydrangeaceae-Loasaceae, and Grubbiaceae-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.

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External links

• http://www.britannica.com/EBchecked/topic/137865/Cornales

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