- Alismatales
Taxobox
name = Alismatales
image_caption = "Alisma plantago-aquatica "
image_width = 300px
regnum =Plant ae
divisio = Magnoliophyta
classis = Liliopsida
ordo = Alismatales
ordo_authority = Dumort.
subdivision_ranks = Families
subdivision = See textAlismatales is an order of
flowering plant s. The order will of necessity contain the familyAlismataceae .Taxonomy
The
APG II system , of 2003 (unchanged from theAPG system , of 1998) assigns the order to the clademonocots and uses this circumscription:
* order Alismatales
*: familyAlismataceae
*: familyAponogetonaceae
*: familyAraceae
*: family Butomaceae
*: familyCymodoceaceae
*: familyHydrocharitaceae
*: familyJuncaginaceae
*: familyLimnocharitaceae
*: familyPosidoniaceae
*: familyPotamogetonaceae
*: familyRuppiaceae
*: familyScheuchzeriaceae
*: familyTofieldiaceae
*: familyZosteraceae Thus circumscribed, the order contains about 165 genera in 14 families, with a
cosmopolitan distribution . Most of the families are composed ofherbaceous plants, commonly found in aquatic environments. Theflower s are usually arranged ininflorescence s, and the mature seeds lackendosperm .The biggest departure from earlier systems (see below) is the inclusion of family
Araceae . By its inclusion the order has grown enormously in number of species. The family Araceae alone accounts for about a hundred genera, totalling over two thousand species. The rest of families together contain just about five hundred species.The
Cronquist system of 1981 placed the order in subclassAlismatidae of classLiliopsida [= monocotyledons] and used this circumscription:
* order Alismatales
*: familyAlismataceae
*: familyButomaceae
*: familyLimnocharitaceae The Cronquist subclassAlismatidae conformed fairly closely to the order Alismatales as circumscribed by APG, minus the family Araceae.The
Dahlgren system placed the order in the superorderAlismatanae in the subclassLiliidae [= monocotyledons] in the classMagnoliopsida [= angiosperms] ; it used this circumscription:
* order Alismatales
*: familyAlismataceae
*: familyAponogetonaceae
*: familyButomaceae
*: familyHydrocharitaceae
*: familyLimnocharitaceae The Dahlgren superorder Alismatanae conformed fairly closely to the order Alismatales as circumscribed by APG, minus the family Araceae.The
Wettstein system , last version in 1935, and theEngler system , update in 1964, used the nameHelobiae for the order.References
*
* ISBN 0-87893-403-0.External links
* [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Undef&id=16360&lvl=3&lin=f&keep=1&srchmode=1&unlock NCBI Taxonomy Browser]
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