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Alismatanae

William J. Hahn
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taxon links [down<--]Monocotyledons Interpreting the tree
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Containing group: Monocotyledons

Introduction

The pondweeds and relatives are almost exclusively aquatic or marine and show numerous specializations for this habitat. Many of these features are reductions in form which have confounded attempts at phylogenetic resolution for the group (Dahlgren and Rasmussen, 1983; Les and Haynes, 1995). The superorder includes 15 families, 56 genera, and approximately 500 species.

Characteristics

Morphological synapomorphies for the alismatids include presence of intravaginal squamulae, lack of an endosperm, and root hair cells shorter than epidermal cells. (Dahlgren and Rasmussen, 1983; Dahlgren et al, 1985; Dalgren and Bremer, 1985).

Discussion of Phylogenetic Relationships

This reconstruction is taken from Les and Haynes (1995) and is based on rbcL data.

References

Dahlgren, RMT & K Bremer. 1985. Major clades of the angiosperms. Cladistics 1: 349-368.

Dahlgren, RMT, HT Clifford, & PF Yeo. 1985. The Families of the Monocotyledons. 520 pp. Springer-Verlag, Berlin.

Dahlgren, RMT, & F Rassmussen. 1983. Monocotyledon evolution. Characters and phylolgenetic estimation. Evol. Biol. 16: 255-395.

Les, DH & RR Haynes. 1995. Systematics of subclass Alismatidae: A synthesis of approaches. pp 353-377 in PJ Rudall, PJ Cribb, DF Cutler, & CJ Humphries (eds). Monocotyledons: systematics and evolution. Royal Botanic Garden, Kew.

Title Illustrations
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Scientific Name Sagittaria montevidensis
Location cultivated at Fairchild Tropical Botanic Garden, Miami, USA
Specimen Condition Live Specimen
Body Part flowers
Source Sagittaria montevidensis male
Source Collection Flickr
Image Use creative commons This media file is licensed under the Creative Commons Attribution License - Version 2.0.
Copyright © 2005 Scott
Scientific Name Halophila ovalis
Location Fly Point, Port Stephens, New South Wales, Australia
Specimen Condition Live Specimen
Source Broadleaf Seagrass
Source Collection Flickr
Image Use creative commons This media file is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike License - Version 2.0.
Copyright © 2007 Richard Ling
Scientific Name Butomus umbellatus
Location Ithaca, New York, USA
Specimen Condition Live Specimen
Body Part flowers
Source Prettiest rush ever...
Source Collection Flickr
Image Use creative commons This media file is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike License - Version 2.0.
Copyright © 2007 Jenn Forman Orth
About This Page


Georgetown University, Washington, D. C., USA

Correspondence regarding this page should be directed to William J. Hahn at

Page: Tree of Life Alismatanae. Authored by William J. Hahn. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.

Citing this page:

Hahn, William J. 1997. Alismatanae. Version 01 January 1997 (under construction). http://tolweb.org/Alismatanae/21329/1997.01.01 in The Tree of Life Web Project, http://tolweb.org/

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For a more detailed explanation of the different ToL page types, have a look at the Structure of the Tree of Life page.

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