The Asteridae
Family Overview - Lamiales

Boraginaceae - the Borage Family

Diversity:  Shrubs, trees and - especially in our flora - herbs in about 100 genera and 2,000 species.

Distribution:  Worldwide, but with greatest diversity in the Mediterranean basin. We have 19 genera and 74 species in the Texas flora

Floral structure:

Significant features:  This family carries the distinctive gynoecium of the Lamiales.  The ovary shows a second septum, producing 4 locules and each of these has only a single seed.  The pericarp is formed around each seed and, as a result, the gynoecium shows a 4-lobed aspect with a depression at the center.  The syle is therefore not attached to the top of the ovary, but rather in this central area.  This unusual feature, knows as a gynobasic style, is also present in the Lamiaceae.  However, in contrast to the other two families of the Lamiales, the Boraginaceae shows three distingishing features:  actinomorphic corolla, alternate leaves and a terete stem. Also, as depicted below, many species of this family produce an inflorescence that uncurls as it develops - the helicoid or scorpiod cyme. It is also common for flowers of the Boraginaceae to show a series of 'bumps' - termed appendages - at the throat of the corolla and a rough, bristly pubescence.
 
 

Symphytum officinale - common comfrey - overview from  Otto Wilhelm Thomé's - Flora von Deutschland Österreich und der Schweiz (1885 - 1905) and photo of inflorescences (right)

Local Endemic - Onosmodium bejariense


plant
helicoid cyme
helicoid cyme - close

Hackelia

helicoid cymes uncurled
flowers with bumpy 'appendages' at the throat of the corolla
four parted fruit with each 'nutlet' carrying a single seed

More information on the Boraginaceae


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