Ulvophyceae

Ulvophyceae
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Ulvophyceae diversity
Scientific classification
Domain:	Eukaryota
Kingdom:	Viridiplantae
Division:	Chlorophyta
Class:	Ulvophyceae Stewart & Mattox, 1978
Orders
Bryopsidales Cladophorales Dasycladales Oltmannsiellopsidales Scotinosphaerales Trentepohliales Ulotrichales Ulvales

The Ulvophyceae or ulvophytes are a class of green algae, distinguished mainly on the basis of ultrastructural morphology, life cycle and molecular phylogenetic data. The sea lettuce, Ulva, belongs here. Other well-known members include Caulerpa and Acetabularia and Monostroma kuroshiensis.

The Ulvophytes are diverse in their morphology and their habitat. Most are seaweeds such as those listed above. Others, such as Rhizoclonium, Pithophora and some species of Cladophora live in fresh water and in some areas are considered weeds.

Evolution

The origin and early diversification of the Ulvophyceae likely took place in the late Neoproterozoic. Although most contemporary ulvophytes are marine macroalgae (seaweeds), ancestral ulvophytes may have been freshwater, unicellular green algae. Molecular phylogenetic evidence suggests that macroscopic growth was achieved independently in the various major lineages of Ulvophyceae (Ulvales-Ulotrichales, Trentepohliales, Cladophorales, Bryopsidales and Dasycladales).

Current hypothesis on relationships among the main clades of Ulvophyceae are shown below.

	Cladophorales Blastophysa Dasycladales Bryopsidales Trentepohliales Ignatius clade Ulvales Phaeophila, Bolbocolean Ulotrichales Desmochloris, Halochlorococcum Scotinosphaerales Oltmannsiellopsidales