Monterey Bay Aquarium Research Institute
Marine Botany

Enteromorpha Classification

UPDATE: Enteromorpha: synonymous with the genus Ulva

See Linnaeus was right all along: Ulva and Enteromorpha are not distinct genera. Eur. J. Phycol (August 2003) 38: 277-293.

Old text: Algae are difficult organisms to classify, due at least in part to the possibility that algae have actually evolved more than once and so are not necessarily all descended from the same ancestor. Enteromorpha in particular is a difficult genus to divide into species because the morphology of the different species tends to vary widely in nature. Sometimes the only way to tell different species apart is to use molecular sequence data. Because of this, it can be difficult to determine the species of a member of the genus Enteromorpha in the field. Enteromorpha is also similar to Ulva, and it is sometimes difficult to differentiate between the two different genuses. It is important to remember that Enteromorpha is tubular (although the tubes are often partially compressed), and the walls of the tube are only one cell layer thick, while Ulva has flat blades that are two cell layers thick.

Different publications have classified Enteromorpha in different ways, however, the following classification seems to be the most common:

Kingdom............................Protista
Phylum..............................Chlorophyta
Class..................................Chlorophyceae
Order.................................Ulotrichales
Family................................Ulvaceae
Genus...............................Enteromorpha

In California, the most common species of Enteromorpha are E. intestinalis, E. clathrata, E. compressa, E. flexuosa, E. linza, and E. prolifera. Most of the Enteromorpha pictured on this website belong to the species intestinalis, however, other species are pictured as well.

Last updated: Feb. 05, 2009