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The Malvales are an order of flowering plants, mostly comprised of shrubs and trees. Most of its families have cosmopolitan distribution in the tropic and subtropic climates, with limited expansion to temperate or cold regions. An interesting distribution emphasis is placed on Madagascar, as there are three families (Sphaerosepalaceae, Sarcolaenaceae and Diegodendraceae) endemic to it.
The order accounts for about 6000 species in nine families. The dominant family is the extended Malvaceae with over 4000 species, followed by Thymelaeaceae with 750 species.
The morphology of Malvales is diverse, and there are few common properties. Among most commonly encountered characteristics one can mention palmate or palmately lobed leaves, connate sepals, and a specific structure and chemical composition of the seeds. The cortex is often fibrous, built of soft phloem layers.
Many Malvales species are known for their wood, of exceptional quality and lightness (namely Ochroma, Edgeworthia, Tilia, Thymelaea and Daphne). The cacao tree (Theobroma cacao) is used as an ingredient for chocolate. Kola nuts (genus Cola) are notable for their high content of caffeine, and in past were commonly used for preparing of various cola drinks.
Newer systems place Malvaceae among the rosid group of dicotyledons.
The Malvaceae is taken to include the older families Bombaceae , Sterculiaceae , and Tiliaceae . Under the older Cronquist system, the order contained only these four families and the Elaeocarpaceae, and was placed among the Dilleniidae . Some of the current families were placed by Cronquist in the Violales.
- Alverson, W. S., K. G. Karol, D. A. Baum, M. W. Chase, S. M. Swensen, R. McCourt, and K. J. Sytsma (1998). Circumscription of the Malvales and relationships to other Rosidae: Evidence from rbcL sequence data. American Journal of Botany 85, 876-887. (Available online: Abstract)
- W. S. Judd, C. S. Campbell, E. A. Kellogg, P. F. Stevens, M. J. Donoghue (2002). Plant Systematics: A Phylogenetic Approach, 2nd edition. pp. 405-410 (Malvales). Sinauer Associates, Sunderland, Massachusets. ISBN 0878934030.
- B. C. J. du Mortier (1829). Analyse des Familles de Plantes, avec l'indication des principaux genres qui s'y rattachent, p. 43. Imprimerie de J. Casterman, Tournay.
- B. A. Whitlock (October 2001). Malvales (Mallow). In: Nature Encyclopedia of Life Sciences. Nature Publishing Group, London. (Available online: DOI | ELS site)
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