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Electronic Flora of South Australia Species Fact Sheet

Centroceras clavulatum (C. Agardh) Montagne 1846: 140.

Phylum Rhodophyta – Order Ceramiales – Family Ceramiaceae – Tribe Ceramieae

Selected citations: J. Agardh 1851: 148; 1876: 108. De Toni 1903: 1491. Harvey 1855a: 557; 1859b: 329; 1863, synop.: xlvii. Hommersand 1963: 241, figs 29, 30a, pl. 3b. Huisman & Walker 1990: 420. Millar 1990: 390, fig. 40E–G. Millar & Kraft 1993: 37. Silva et al. 1996: 387. Sonder 1881: 13.


Ceramium clavulatum C. Agardh 1822: 2. Lucas 1909: 53; 1929a: 26. Lucas & Perrin 1947: 370.

Ceramium cryptocanthum (Kützing) Sonder 1848: 167.

Ceramium hyalacanthum (Kützing) Sonder 1848: 167.

Centroceras cinnabarinum sensu Harvey 1863, synop.: xlvii. Lucas 1909: 53. Sonder 1881: 13. [NON C. cinnabarinum (Grateloup) J. Agardh 1851: 148]

Ceramium cinnabarinum sensu Lucas & Perrin 1947: 370.

Callithamnion ramellosum Sonder 1848: 166; 1881: 10. J. Agardh 1851: 66. De Toni 1903: 1335 (both as C. ramulosum). See Silva et al. (1996, pp. 387–389) for the extensive synonymy and references for this species.

Thallus (Fig. 19] A) dark red-brown, usually densely tufted, 2–8 (–15) cm high, fastigiate and usually even topped with straight, terete, largely subdichotomous filaments 100–180 µm in diameter, completely corticated, with few adventitious laterals, apices involute with short abaxial spines. Attachment by rhizoids with multicellar pads, arising from slight prostrate filaments; epilithic or epiphytic on larger algae or sea-grasses. Structure. Apical cells shortly conical, 10–15 µm in basal diameter, enlarging rapidly to axial cells 40–90 µm in diameter and L/D (1–) 2–3, with central longitudinal protoplasmic strands, and with 12–14 periaxial cells (Fig. 191B) formed in alternating sequence, these each cutting off 2 short cells acropetally and 2 (sideways and basipetally), rarely 3, which form 24–29 (Fig. 191C) unbranched closely adjacent, corticating rows of small, rectangular cells (Fig. 191E, G) 8–12 µm in diameter and L/D 1–2 (–3). Spines abaxial and unilateral near apices, sometimes opposite, originating from a periaxial cell, 1–3 (–4) cells and 20–45 µm long, usually lost from lower nodes. Elongate-clavate hairs frequent to absent. Branching subdichotomous at apical cells or lateral from periaxial cells. Rhodoplasts discoid.

Reproduction: Gametophytes dioecious. Carpogonial branches on the first formed periaxial cells. Carposporophytes (Fig. 191D) with 1–2 rounded gonimolobes 250–450 µm across, carposporangia ovoid, 25–45 µm in diameter, with 2–5 involucral branches from below. Spermatangia in dense sori (Fig. 191E) around the nodes, borne on branched filaments from the periaxial cells (Fig. 191F).

Tetrasporangia (Fig. 191G) first abaxial but soon becoming whorled at the nodes, cut off from periaxial cells, without or with short involucral filaments, subspherical to pyriform, 40–70 µm in diameter, tetrahedrally divided.

Type from Callao, Peru (Humboldt); holotype in Herb. Agardh, LD (see Howe 1911, p. 509).

Selected specimens: Point Peron, W. Aust., on reef (Cribb 69.25, 15.viii.1950; AD, A13973). Marmion, W. Aust., lower eulittoral (Womersley, 13.ix.1979; AD, A50991). Cape Le Grand, W. Aust., lower eulittoral (Woelkerling, 28.i.1978; AD, A49285). Point Sinclair, S. Aust., mid eulittoral, on granite and Hormosira (Womersley, 7.ii.1954; AD, A19579 and A19562 resp.). Coffin Bay, S. Aust., upper sublittoral (Womersley, 13.v.1968; AD, A32486). Wanna, S. Aust., lower eulittoral (Gordon, 15.v.1968; AD, A32963) and (Ricci, 13.ii.1994; AD, A63365). Troubridge Point, S. Aust., >mid eulittoral (Shepherd, 7.ii.1969; AD, A33836-"Marine Algae of southern Australia" No. 105). American R. inlet. Kangaroo I., S. Aust., mid eulittoral near jetty (Womersley, 17.viii.1948; AD, A8538). Ellen Point, Vivonne Bay, Kangaroo I., S. Aust., in shallow pool (Womersley, 25.x.1995; AD, A64660). Antechamber Bay, Kangaroo I., S. Aust., upper sublittoral on piles (Parsons, 20.xi.1967; AD, A32095). Robe, S. Aust., pools on slipway reef (Womersley, 13.v.1972; AD, A42245). Lake Butler, Robe, S. Aust., upper sublittoral (Womersley, 5.xii.1995; AD, A64742). Bridgewater Bay, Vic., lower eulittoral (Womersley, 21.viii.1953; AD, A19050). Dromana, Port Phillip, Vic., upper sublittoral (Sinkora A2462, 23.xi.1978; AD, A60901). Bridport, Tas., low eulittoral pool (Womersley, 13.x.1994; AD, A64200). Bicheno, Tas., mid eulittoral (Bennett, 6.ii.1955; AD, A20663).

Distribution map based
on current data relating to
specimens held in the
State Herbarium of SA

Distribution: Widely distributed on most tropical to temperate coasts. Generally around Australia.

Taxonomic notes: Centroceras clavulatum is a common epilithic alga in the lower eulittoral zone and just below, forming dense, dark red-brown, tufts, and also occurs as smaller plants on a variety of larger algae (e.g. Hormosira) and robust sea-grasses.

Centroceras cinnabarinum was recorded by Harvey (1863, synop.: xlvii) from St Kilda, Port Phillip, Vic. (Watts), and reported by Lucas & Perrin (1947, p. 370) as a Ceramium. The Watts specimen (fragment in AD, A18561) appears to be typical Cent. clavulatum but with spines generally absent.

The type of Callithamnion ramellosum Sonder (MEL, 573179) from W. Asut., (Preiss) is Centroceras clavulatum.


AGARDH, J.G. (1851). Species Genera et Ordines Algarum. Vol. 2, Part 1, I-XII, 1–336 + index. (Gleerup: Lund.)

AGARDH, J.G. (1876). Species Genera et Ordines Algarum. Vol. 3, Part 1- Epicrisis systematic Floridearum, pp. i-vii, 1–724. (Weigel: Leipzig.)

DE TONI, G.B. (1903). Sylloge Algarum omnium hucusque Cognitarum. Vol. 4. Florideae. Sect. 3, pp. 775–1521 + 1523–1525. (Padua.)

HARVEY, W.H. (1855a). Some account of the marine botany of the colony of Western Australia. Trans. R. Jr. Acad. 22, 525–566.

HARVEY, W.H. (1859b). Algae. In Hooker, J.D., The Botany of the Antarctic Voyage. III. Flora Tasmaniae. Vol. II, pp. 282–343, Plates 185–196. (Reeve: London.)

HARVEY, W.H. (1863). Phycologia Australica. Vol. 5, Plates 241–300, synop., pp. i-lxxiii. (Reeve: London.)

HOMMERSAND, M.H. (1963). The morphology and classification of some Ceramiaceae and Rhodomelaceae. Univ. Calif Pubis. Bot. 35(2), 165–366.

HOWE, M.A. (1911). Phycological studies V. Some marine algae of Lower California, Mexico. Bull. Torrey Bot. Club 38, 489–514, Plates 27–34.

HUISMAN, J.M. & WALKER, D.I. (1990). A catalogue of the marine plants of Rottnest Island, Western Australia, with notes on their distribution and biogeography. Kingia 1, 349–459.

LUCAS, A.H.S. & PERRIN, F. (1947). The Seaweeds of South Australia. Part 2. The Red Seaweeds. (Govt Printer: Adelaide.)

LUCAS, A.H.S. (1909). Revised list of the Fucoideae and Florideae of Australia. Proc. Linn. Soc. N.S.W. 34, 9–60.

LUCAS, A.H.S. (1929a). The marine algae of Tasmania. Pap. Proc. R. Soc. Tasm. 1928, 6–27.

MILLAR, A.J.K. & KRAFT, G.T. (1993). Catalogue of marine and freshwater Red Algae (Rhodophyta) of New South Wales, including Lord Howe Island, South-western Pacific. Aust. Syst. Bot. 6, 1–90.

MILLAR, A.J.K. (1990). Marine red algae of the Coffs Harbour region, northern New South Wales. Aust. Syst. Bot. 3, 293–593.

MONTAGNE, C. (1846). Algues. In Durieu de Maisonneuve, M.C., Exploration scientifique de l'Algérie. Bot. I., pp. 121–160. (Imprimerie Imperiale: Paris.)

SILVA, P.C., BASSON, P.W. & MOE, R.L. (1996). Catalogue of the Benthic Marine Algae of the Indian Ocean. (University of California Press: Berkeley, Los Angeles & London.)

SONDER, O.W. (1848). Algae. In Lehmann, C., Plantae Preissianae. Vol. 2, pp. 161–195. (Hamburg.)

SONDER, O.W. (1881). In Mueller, F., Fragmenta Phytographiae Australiae. Supplementum ad volumen undecinum: Algae Australianae hactenus cognitae, pp. 1–42, 105–107. (Melbourne.)

The Marine Benthic Flora of Southern Australia Part IIIC complete list of references.

Author: H.B.S. Womersley

Publication: Womersley, H.B.S. (24 December, 1998)
The Marine Benthic Flora of Southern Australia
Rhodophyta. Part IIIC. Ceramiales – Ceramiaceae, Dasyaceae
©State Herbarium of South Australia, Government of South Australia

Illustration in Womersley Part IIIA, 1998: FIG. 191.

Figure 191 image

Figure 191   enlarge

Fig. 191. Centroceras clavulatum (A, AD, A32095; B, C, AD, A63365; D–F, AD, A49285; G, AD, A32486). A. Habit. B. Transverse section through node with 13 periaxial cells, cortical cells partly hidden. C. Transverse section between nodes, with 26 cortical cells. D. Branch with carposporophytes. E. Branch of male plant with nodal spermatangia. F. Longitudinal section of male branch showing origin of spermatangial clusters from periaxial cells. G. Branches with tetrasporangia.

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