Electronic Flora of South Australia Genus Fact Sheet

Genus BOSTRYCHIA Montagne 1842a: 39, nom. cons.

Phylum Rhodophyta – Family Rhodomelaceae – Tribe Bostrychieae

Thallus dorsiventrally developed, apices straight or usually curved to circinnate, with prostrate and erect indeterminate axes bearing simple or branched determinate laterals usually at regular intervals. Attachment by rhizoidal haptera borne terminally on special branches ("cladohaptera") or as clusters from pericentral or cortical cells ("peripherohaptera"); epiphytic or epilithic. Structure. Apical cells prominent, with thick walls. Pericentral cells 4–9, each dividing transversely into 2 tiers, the basal cell remaining pit-connected with the axial cell; ecorticate or corticate. Branching exogenous, rarely endogenous. Trichoblasts absent.

Reproduction: Gametophytes monoecious or (usually) dioecious. Procarps formed in series on polysiphonous determinate branches, with 1–4 per segment, each procarp with a single sterile group and (3–) 4-celled carpogonial branch. Carposporophyte with a short, branched gonimoblast bearing clavate terminal carposporangia. Cystocarps subterminal, ovoid to subspherical; pericarp initiated post-fertilization, with 6–14 longitudinal filaments, corticated. Spermatangia superficial on corticated polysiphonous determinate laterals with or without a sterile tip.

Tetrasporangia whorled, borne in stichidia on determinate laterals, up to 25 segments long, fertile segments with 4–5 pericentral cells and tetrasporangia, each protected by 2–3 cover cells which are often subdivided.

Lectotype species: B. scorpioides (Hudson) Montagne (Kützing 1849: 839).

Taxonomic notes: A genus of numerous species, differing from Stictosiphonia in having pericentral cells dividing transversely into only 2 tiers instead of 4–5. The Australian species were described by King & Puttock (1989) and their account is followed here.

References:

KÜTZING, F.T. (1849). Species Algarum. (Leipzig.)

KING, R.J. & PUTTOCK, C.F. (1989). Morphology and taxonomy of Bostrychia and Stictosiphonia (Rhodomelaceae / Rhodophyta). Aust. Syst. Bot. 2, 1–73.

MONTAGNE, C. (1842a). Botanique. Plantes cellulaires. In Sagra, R. de la, Histoire physique, politique et naturelle de Pile de Cuba. (Paris.)

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

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.

KEY TO SPECIES OF BOSTRYCHIA

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