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Chlorophyta, Green Algae

Ulva (Enteromorpha) ramulosa (J. E. Smith) Carmichael

Chlorophyta, Order: Ulvales; Family: Ulvaceae.

Current accepted name: Ulva ramulosa (Roth) C. Agardh


Ulva (Enteromorpha) refers to the thallus’ tubular shape, which resembles an intestine. The name of the species refers to the copious branching of the thallus.


The Ulva (Enteromorpha) ramulosa has a thin filamentous thallus with copious branching. The branches are sharp and resemble (microscopic) pedicles. An overview of the thallus’ underside reveals cells scattered irregularly. However, on the upper side they are arranged in rows. The cells are diamond-shaped and rounded. The chloroplast is dented. There are usually several Pyrenoids from 2-10.


The Ulva (Enteromorpha) ramulosa is a relatively small alga. Its thallus does not grow larger than 10 cm, and the strand is several millimetres wide.

Ulva (Enteromorpha) ramulosa -an overview of the thallus’ lower segment: cells are dispersed. In the upper section of the thallus’ some are arranged in rows.

Ulva (Enteromorpha) ramulosa

structure of the thallus with side branching.


The Ulva (Enteromorpha) ramulosa is usually shaded light green.

Special features

The Ulva (Enteromorpha) ramulosa’s most distinguishing feature is its thorny branching. A microscope is required to see these.


There is insufficient data regarding the species’ distribution in the Eastern Mediterranean, but it seems that the Ulva (Enteromorpha) ramulosa grows in the upper region of the intertidal zone upon sandy or sand-covered rocky substrates.

Biology and reproduction

Similar to Ulva and Enteromorpha (see entry.(

Seasonality and distribution

As far as known, this is the first description of Ulva (Enteromorpha) ramulosa along Israeli coasts. I first collected the species at Rosh Hanikra from a sandy substrate. The species is universally distributed. It may have pre-existed, but was unidentified.

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