Laurales

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Laurales is the botanical name of an order of flowering plants. It will always include the family Lauraceae (the Bay laurel family). This order has not always been recognised by systems of plant taxonomy, these plants sometimes being included in order Magnoliales.

The APG II system, of 2003 (unchanged from the APG system, of 1998), places the order in the clade magnoliids (thus excluded from the eudicots) and uses this circumscription:

order Laurales
: family Atherospermataceae
: family Calycanthaceae
: family Gomortegaceae
: family Hernandiaceae
: family Lauraceae
: family Monimiaceae
: family Siparunaceae

This order includes about 2500-2800 species from 85-90 genera, which comprise seven families of trees and shrubs. Most of the species are tropical and subtropical, though a few genera reach the temperate zone.

The earliest lauraceous fossils are from to the early Cretaceous. It is possible that the ancient origin of this order is one of the reasons for its highly diverged morphology. Indeed, presently no single morphological character is known which would unify all the plants present in these Laurales.

This placement and circumscription is exactly the same as in the APG system, of 1998.

The Cronquist system, of 1981, placed the order in the subclass Magnoliidae of class Magnoliopsida [=dicotyledons] and used this circumscription:

order Laurales
: family Amborellaceae
: family Calycanthaceae
: family Gomortegaceae
: family Hernandiaceae
: family Idiospermaceae
: family Lauraceae
: family Monimiaceae
: family Trimeniaceae

The alteration by APG is not as large as may seem: the plants in families Atherospermataceae and Siparunaceae were already present in Cronquist's family Monimiaceae. Cronquist's family Idiospermaceae has stayed to become part of family Calycanthaceae.

References

K.J. Perleb (1826). Lehrbuch der Naturgeschichte des Pflanzenreichs p. 174. Magner, Freiburg im Breisgau, Deutschland.
Renner, Susanne S. (May 2001) Laurales. In: Nature Encyclopedia of Life Sciences. London: Nature Publishing Group. [doi:10.1038/npg.els.0003695 Abstract], [Full text (pdf)].
Renner S.S. (1999). Circumscription and phylogeny of the Laurales: evidence from molecular and morphological data. American Journal of Botany 86 (9): 1301-1315. [Abstract], [Full text (pdf)].
Endress P.K., Igersheim A. (1997). Gynoecium diversity and systematics of the Laurales. Botanical Journal of the Linnean Society 125 (2): 93-168. [doi:10.1006/bojl.1997.0113 Abstract].

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