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Name derivation:

Ceramium = Gr. keras: a horn + L. ium: a collection; “like a small pitcher”

virgatum = L. virgatum: twiggy, long and slender, streaked, or rod-like

Common names: banded weed or pottery seaweed


Ceramium  Roth 1797;  207 of 914 species descriptions are currently accepted taxonomically (Guiry and Guiry 2016).

Subclass Florideophyceae; Order Ceramiales; Family Ceramiaceae


Filaments terminate in caliper-like tips; they are uniseriate, stiff, coarse, pale to black or rose-red, 18-40 cm tall, and attached by a tuft of rhizoids.  Axes are alternately branched below, subdichotomous to trichotomous above, wide spreading, and completely corticated up to 2 cells below the apical cell.  Tetrasporangia are tetrahedrally divided. Gametophytes are dioecious.

Similar genera:



In the Northwest Atlantic Ceramium virgatum is often very common, occurring as an aseasonal annual. Growing on rocks, shells, pilings, and most often on other larger seaweeds. Occurring in the mid-littoral pools and extending to ~ 20m subtidally.  Found in exposed or sheltered open coastal areas and tolerant of estuarine waters.

Also found in the Dry tortugas, Bermuda, Dominican Republic, Gulf of Mexico, Brazil, Tanzania, theSeychelles and Fiji (Dawes and Mathieson 2008).  Widespread in subtropical to tropical seas.


Dawes, C. J. and A. C. Mathieson. 2008. The seaweeds of Florida. Univ. Press of Florida, Gainesville, Florida, 591 pp.

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.

Maggs, C.A.  and M. H. Hommersand. 1993. Seaweeds of the British Isles. Volume 1. Rhodophyta. Part 3A. Ceramiales. British Mus. (Nat. Hist.), London. xv + 444 pp.

Taylor, W. R.  1957. Marine Algae of the Northeastern Coast of North America. Revised edition. Univ. Michigan Press., Ann Arbor, ix + 509 pp.

Roth, A.W.  1797.  Catalecta botanica quibus plantae novae et minus cognitae describuntur atque illustrantur. Fasc. 1. pp. [i]-viii, [1]-244 [1-2, index, pls], pls I-VIII. Lipsiae [Leipzig]: in Bibliopolo I.G. Mülleriano.