Gelidium

Gelidium
Scientific classification
Domain:	Eukaryota
(unranked):	Archaeplastida
Division:	Rhodophyta
Class:	Rhodophyceae
Subclass:	Rhodymeniophycidae
Order:	Gelidiales
Family:	Gelidiaceae
Genus:	Gelidium J.V. Lamouroux, 1813

Gelidium is a genus of thalloid red algae comprising 124 species. Its members are known by a number of common names. Specimens can reach around 2–40 cm (0.79–16 in) in size. Branching is irregular, or occurs in rows on either side of the main stem. Gelidium produces tetraspores. Many of the algae in this genus are used to make agar. Chaetangium is a synonym.

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