A small green alga (up to 30 cm long) with a dichotomously branched, cylindrical frond. The frond is solid and spongy with a felt-like touch and has many colourless hairs which can be seen when the plant is immersed in water. The holdfast is disc-like and formed from many fine threads.

Codium tomentosum can be confused with Codium fragile. However, Codium tomentosum tends to have a more slender frond with rounded tips whereas Codium fragile has pointed tips to the frond.

Link for (Pereira, 2010) Handbook Guide

Original publication: Stackhouse, J. (1797). Nereis britannica; continens species omnes fucorum in insulis britannicis crescentium: descriptione latine et anglico, necnon iconibus ad vivum depictis... Fasc. 2. pp. ix-xxiv, 31-70, pls IX-XIII. Bathoniae [Bath] & Londini [London]: S. Hazard; J. White.

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Codium tomentosum is a small green seaweed in the family Codiaceae in the Phylum Chlorophyta, which grows to 30 centimeters in length. The genus is Greek for kodion, meaning small sheepskin. It is dark green, similar to a green bottle. The thallus or frond has a dichotomous, much-branched structure with thin branches or fronds, which are cylindrical and from 8 to 10 millimeters in diameter. The fronds are solid and spongy with a felt-like or velvety touch, and are covered with colourless hairs which are visible when it is submerged. The holdfast of Codium tomentosum is disc- or saucer-shaped, and has closely woven threads or strands, giving it a uniform appearance. Codium tomentosum is a perennial species of the infra-littoral, and attaches to exposed rocks and occurs in deep rock pools on the lower shore.

Link for Seaweeds Industry Association

Direct use as food - food, consumed whole; Contains: retinol and derivatives (vitamin A).

Provide biological, medical and pharmacological activity - antihelminthic (vermifuge).

Newton, L.M. (1953). Marine algae. In: The John Murray Expedition 1933-34 scientific reports. ( Eds) Vol.9, pp. 395-420. London:

Zemke-White, W.L. & Ohno, M. (1999). World seaweed utilisation: an end-of-century summary. Journal of Applied Phycology 11: 369-376.

In English: Spongeweed, Velvet horn

In Portuguese: Chorão-do-mar

Type species: This is the type species (holotype) of the genus Codium

Type locality: England (Silva, Basson & Moe 1996: 864).

Neotype: LINN (Silva 1955: 571).

Notes: The neotype was selected from specimens in Stackhouse’s herbarium and is likely to be from Cornwall.

Taxonomic notes: According to Silva et al. (1996) the name Codium dichotomum has been misapplied to this species by Børgesen (1949a: 22-23) and Brown & Jarman (1978: 1256).