Electronic Flora of South Australia Genus Fact Sheet

Genus ENDOSIPHONIA Zanardini 1878: 35

Phylum Rhodophyta – Family Rhodomelaceae – Tribe Lophothalieae

Thallus erect or entangled, much branched, branches rigid, drying cartilaginous, terete, with short, spinous, ultimate laterals; attachment by rhizoids or a fibrous holdfast. Structure. Apical cell segmenting transversely, subapical cells cutting off trichoblasts and 4 pericentral cells undivided transversely but forming a broad small-celled cortex. Trichoblasts probably also exogenous from epidermal cells, simple or basally branched, cells with rhodoplasts.

Reproduction: Gametophytes dioecious. Procarps borne on lower cells of trichoblasts, soon surrounded by 5 pericentral cells. Carposporophytes with a basal fusion cell and branched gonimoblast with terminal carposporangia. Cystocarps ovoid to slightly urceolate, ostiolate, with cells of the erect filaments cutting off 2 isodiametric outer cells and a cortex 1–2 cells thick. Spermatangia covering lower parts of trichoblasts, with a monosiphonous pedicel and emergent monosiphonous filaments.

Tetrasporangia produced in polysiphonous segments of trichoblasts, stichidia with a monosiphonous pedicel and simple filaments usually on each segment, developed from meristematic apices, with 2–3 cover cells.

Type species: E. spinuligera Zanardini 1878: 35 [= ?E. spinulosa (Harvey) Womersley, comb. nov.]

Taxonomic notes: A genus of 5–8 species, the type from the Aru Islands of Irian Jaya, also known from northern Australia (Millar 1990, p. 453; Huisman 2000, p. 178) and the tropical Indo-Pacific. It appears probable that E. spinulosa (Harvey) Womersley & Parsons, comb. nov., described below, is the same as the type and an older name.

Endosiphonia almost certainly includes Spirocladia Børgesen (1933b, p. 14, figs 1–10), the differences recognised by Kylin (1956, p. 496) - branching of trichoblasts and their presence or not on stichidia, presence or not of spines - are not satisfactory considering the account of Nasr (1938) of E. clavigera (Wollny) Falkenberg. Spirocladia includes the type, S. barodensis from India, S. minor Nasr (1939, p. 332, figs 1–8) from the Gulf of Suez, S. loochooensis (Yendo) Yoshida (1989, p. 272, figs 1, 2) from Japan, and S. hodgsoniae Abbott (see Abbott 1999, p. 438) from the Hawaiian Is.

Endosiphonia is characterised by having trichoblasts which become basally and spirally branched, with small basal cells and long, unbranched upper branches, by 4 pericentral cells becoming corticated, and by both spermatangial and tetrasporangial branches developed from trichoblasts, with monosiphonous pedicels and bearing simple filaments from each segment.

References:

ABBOTT, I.A. (1999). Marine Red Algae of the Hawaiian Islands. (Bishop Museum Press: Honolulu, Hawai'i.)

BØRGESEN, F. (1933b). On a new genus of the Lophotalieae (Fam. Rhodomelaceae). K. Dan. Vidensk. Selskab. Biol. Medd. 10(8), 1–16.

HUISMAN, J.M. (2000). Marine Plants of Australia. (Univ. W. Aust. Press, Nedlands, W. Aust. & ABRS, Canberra, A.C.T.)

KYLIN, H. (1956). Die Gattungen der Rhodophyceen. (Gleerups: Lund.)

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

NASR, A.H. (1938). A contribution to our knowledge of Endosiphonia Zanard., in relation to its systematic position. Bull. l'Inst. Egypte 20, 123–129, 1 pl.

NASR, A.H. (1939). On a new species of the Rhodomelaceae from Egypt. Rev. Algol. 11, 331–337.

YOSHIDA, T. (1989). Notes on Spirocladia loochooensis (Yendo)Yoshida, comb. nov. (Rhodomelaceae, Rhodophyta). Jap. J. Phycology (Sôrui) 37, 271–273.

ZANARDINI, J. (1878). Phyceae Papuanae novae vel minus cognitae a cl. O. Beccari in itinere ad Novam Guineam annis 1872–75 collectae. Nuovo giornale Bot. Italiano 10, 34–40.

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

Author: H.B.S. Womersley & M.J. Parsons

Publication: Womersley, H.B.S. (24 February, 2003)
The Marine Benthic Flora of Southern Australia
Rhodophyta. Part IIID. Ceramiales – Delesseriaceae, Sarcomeniaceae, Rhodomelaceae
Reproduced with permission from The Marine Benthic Flora of Southern Australia Part IIID 2003, by H.B.S. Womersley. Australian Biological Resources Study, Canberra. Copyright Commonwealth of Australia.

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