Morphology and life history of Predaea kraftiana sp. nov. (Gymnophloeaceae, Rhodophyta) from Australia

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Abstract
Predaea kraftiana sp. nov. is described from the subtidal in the vicinity of Coffs Harbour in northern New South Wales on the east coast of Australia. Thalli are reniform when young, flabellate and lobed when mature; outer cortical cells are cylindrical, the cortical fascicles being pseudodichotomously branched; vesicular cells are absent; carpogonial branches are generally three cells long, but may be two-, four-or five-celled, with an ampulliform basal cell generally bearing a small, sterile cell similar in morphology to the nutritive cells found on cells in the vicinity of auxiliary cells; fertilized carpogonia divide once transversely, each of the resulting cells forming up to three connecting filaments; gonimoblast initials are produced on the lateral surface of the auxiliary cell opposite the site of connecting filament juncture. In culture, carpospores from field-collected gametophytes developed into crustose plants lacking cell fusions or secondary pit-connections. Irregularly to regularly zonately cleaved tetrasporangia were formed on irregularly branched erect filaments at 24°C, 14:10 h, but not at 16°C, 8: 16 h and 18°C, 16: 8 h. Monosporangia were also formed terminally on these filaments. At 24°C, 14: 10 h, but not at 16°C, 8: 16 h and 18°C, 16: 8 h, tetraspores from cultured plants germinated to form small, spherical, gelatinous gametophytes which produced carpogonial branches and spermatangia identical to those found on field-collected plants. Spermatia were not seen attached to trichogynes, auxiliary cells did not develop, and no carposporophytes were produced. Monospores probably formed further tetrasporophytes. The species thus appears to have a Bonnernaisonia hamifera-type life history.