Friday, 11 May 2012


Boraginaceae, the Borage or Forget-me-not family, include a variety of shrubs, trees, and herbs, totaling about 2,000 species in 146 genera found worldwide.  A number of familiar plants belong to this family.
Boraginaceae belong, according to the APG II, among the euasterid I group including the orders Gentianales, Lamiales, and Solanales, but whether they should be assigned to one of these orders or to their own (Boraginales) is still uncertain. Under the older Cronquist system they were included in Lamiales, but it is now clear that they are no more similar to the other families in this order than they are to families in several other asterid orders.

The Boraginaceae are paraphyletic with respect to Hydrophyllaceae and the latter is included in the former in APG II system. In some recent classifications the Boraginaceae are broken up into several families: Boraginaceae s.s., Cordiaceae, Ehretiaceae, Heliotropiaceae, Hydrophyllaceae, and Lennoaceae.
Most though not all members of this family have hairy leaves. The coarse character of the hairs is due to Silicon dioxide and Calcium carbonate. These hairs can induce an adverse skin reaction (itching, rash) in some individuals, particularly among people who handle the plants regularly (e.g. gardeners). In some species, Anthocyanins cause the flowers to change their color from red to blue when aging. This is likely used as a signal to pollinators that these old flowers are depleted of pollen and nectar (Hess, 2005).

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