The Asteridae

Order Overview - The Lamiales

According to Cronquest (1988) the Lamiales "may be briefly characterized as Asteridae with a superior ovary consisting of 2 (-4) biovulate carpels with twice as many uniovulate locelli as carpels.  The fruit very often consists of 1-seeded, half-carpellary nutlets."  From the point of view of field identification, this group of three families is united by the common presence of a gynoecium that differs from those previously considered (Gentianales, Solanales, Scrophulariales) in that the number of ovules has been reduced to four and, via a 'derived' septum, each ovule occuplies its own locule:




Synoptical Arrangement of the Families of the Lamiales

1.  Leaves mostly alternate, flowers actinomorphic, stamens 5, stems terete, gynobasic style present.....  Boraginaceae

1.  Leaves mostly opposite, flowers zygomorphic, stamens less than 5, stems usually quadrangular:

            2.  Style terminal or nearly so, the ovary only shortly or not at all lobed at the top; plants seldom aromatic..... Verbenaceae

            2.  Style commonly gynobasic, uniting otherwise distinct lobes of the ovary; plant usually aromatic.....  Lamiaceae
 


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