The Magnoliidae
Family Overview - The Laurales
Lauraceae - the Laurel Family
Diversity:  30-50 genera with over 2,000 species, nearly all woody (arborescent or fruticose - subfamily Lauroideae) with 1 genus of scandent parasites placed in the other subfamily, the Cassythoideae.

Distribution:  Present in tropical and subtropical areas of both hemispheres and especially diverse in Southeast Asia.  5 genera in the Texas flora, 4 with a single species and Persea with 2.

Floral structure:

Significant features:  'Advanced' floral features include apetaly, 3-merous (monocot-like) whorls in the calyx and androecium with adnation to form an hypanthium; the gynoecium is reduced to a single carpel and the contents of this further reduced to a single ovule.  The anthers also show a strange, pore-flap dehiscence and paired staminodal nectaries are often present at the base of each filament (see Laurus).

  Sassafras albidum - flowers at anthesis - select photo to take a look at the anthers

 This family demonstrates that specialized and derived features occur as a mosaic, i.e., all derived floral structures are not linked to herbaceous elements of the Subclass.  Elements of this family have interesting economic and ethnobotanical connections.  Especially topical, in ancient Greece a wreath made from leaves of the Laurel (Laurus nobilis = type genus) was used as a symbol of honor, and branches were woven into crowns for victors in the ancient Olympic games.  Like many elements of the Subclass, this family is known for the production of volatile oils and we encounter these in cinnamon (Cinnamomum zeylanicum) and the 'root beer' essence of Sassafras albidum which is present in the Texas flora.  The typical fruit type for the family - a drupe - is encountered with the avocado (Persea americana) - the exocarp is peeled, the mesocarp  is fleshy, and the endocarp is reduced to a thin, brown covering of the avocado seed.

More information on the Lauraceae

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9 Feb 2011