Callophycus dorsifer (C.Agardh) P.C.Silva
Taxon 143 (1957)
Conservation Code:
Not threatened
Naturalised Status: Native to Western Australia
Name Status:
Current
Scientific Description
John Huisman & Cheryl Parker,
Monday 20 June 2011
Habit and structure. Thallus dark red-brown, 10–25 cm high, with a short, subterete stipe producing several complanately branched, bipinnate fronds. Axes 5–8 mm broad, with a broad midrib, bearing close set, distichous, subopposite, flat, pinnae which are similarly branched with pinnules also flat and 1–2 mm broad and bearing short ramuli 1–2(–3) mm long forming marginal serrations. Holdfast discoid, 5–15 mm across; epilithic. Structure multiaxial, with a central medullary core of mainly longitudinal, branched filaments and rhizoids, and a pseudoparenchymatous cortex 4–7(–10) cells thick, inner cells ovoid, (12–)20–40 µm in diameter, decreasing to outer cells 2–4 µm in diameter, L/D 1.5–2.5. Rhodoplasts discoid to ribbon shaped, several per cell.
Reproduction. Sexual reproduction non-procarpic. Carpogonial branches 3–4(–5)-celled, borne on an inner cortical cell with the first (and second) cell bearing 1–3 sterile cells, directed inwards and with a reflexed trichogyne. Connecting filaments 4–7, unbranched and non-septate. Auxiliary cells inner cortical cells with adjacent cells darker staining and producing short chains of nutritive cells after diploidization, then producing a gonimoblast initial inwardly which gives a compact group of cells; later gonimoblasts develop radially from the fusion cell which connects to the enlarged axial filament, and produce terminal chains of ovoid carposporangia 5–8 µm in diameter. Cystocarps often crowded, 0.5–1 mm across, protruding, with slight filamentous enveloping tissue, ostiolate. Spermatangia unknown. Tetrasporangia near pinnule ends, subnemathecial, scattered amongst elongate outer cells (L/D 6–8), basally attached, elongate-ovoid, 15–30 µm long and 8–12 µm in diameter, zonately divided.
Distribution. Port Denison to Hamelin Bay, W. Aust.
[After Womersley, Mar. Benthic Fl. Southern Australia IIIA: 333–335 (1994)]
