Electronic Flora of South Australia Genus Fact Sheet
Phylum Phaeophyta – Order Sporochnales
Thallus (sporophyte) 5–20 cm long, much branched irregularly radially with terete branches and well developed apical tufts of assimilatory filaments, attached by a rhizoidal holdfast. Growth apical, with trichothallic filaments surmounting the apex. Structure haplostichous and pseudoparenchymatous, with a core of elongate axial cells, more rounded outer medullary cells, and a cortical layer of papillate, 2–3 celled, filaments covering the surface.
Reproduction: Reproduction by unilocular sporangia scattered amongst the papillate cortical filaments over most of the branches, sessile, clavate to ovoid. Gametophyte (Sauvageau 1927b, p. 357, figs 1,2) microscopic, filamentous, branched, usually dioecious, bearing small, conical antheridia or apical oogonia (which develop apogamously).
Life history diplohaplontic and heteromorphic.
Type species: N. filiformis (J. Agardh) Zanardini.
Taxonomic notes: A genus of 4–5 species, mainly from the Mediterranean but with scattered records from other temperate to tropical waters.
Nereia is characterised by the complete cortical cover of papillate, 2–3 celled, filaments, amongst which are scattered the clavate, sessile, sporangia (Kuckuck 1929, p.77, fig. 109).
KUCKUCK, P. (1929). Fragmente einer Monographie des Pheosporeen. Biol. Anst. Helgol. 17, 1–93.
SAUVAGEAU, C. (1927b). Sur l'alternance des générations chez le Nereia filiformis Zan. Bull. Stn biol. Arcachon 24, 357–367.
ZANARDINI, G. (1846). Sulla Desmarestia filtformis di Giacobbe Agardh e sulle Chordariee in generale. Atti del VII Congresso degli scienziati italiani in Napoli, 1845.
The Marine Benthic Flora of Southern Australia Part II complete list of references.
Womersley, H.B.S. (14 December, 1987)
The Marine Benthic Flora of Southern Australia
©Board of the Botanic Gardens and State Herbarium, Government of South Australia
State Herbarium of South Australia