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Name derivation:

(L.) gelidus gelatinous


Gelidium  J.V. Lamouroux  1813;  104 of 308 species descriptions are currently recognized taxonomically (Guiry and Guiry 2016).

Synonym in PhycoKey:  Plocamion.


Cartilaginous thallus up to 40 cm tall.  One or more erect axes, plumously or irregularly branched, ranging in color from red to dark purple.  Cortex of stem has several rows of smaller cells, 2 – 15 μm and medulla has larger cells up to 30 μm diameter (Ibid.).

Similar genera:

Lamouroux (1813) describes Plocamion (pp 137-138) separately from Gelidium (pp 128-129) and they are both considered taxonomically acceptable, although at least some species are synonymous.  For that reason Plocamion is not separated from Gelidium in PhycoKey.


Intertidal to deep subtidal worldwide from temperate to tropical waters (Ibid.).




Guiry, M.D. and G.M. Guiry  2014.  AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 2 May 2014.

Lamouroux, J.V.F.  1813.  Essai sur les genres de la famille des thalassiophytes non articulées.  Annales du Muséum d'Histoire Naturelle, Paris 20: 21-47, 115-139, 267-293, pls 7-13.