Electronic Flora of South Australia Genus Fact Sheet
Phylum Phaeophyta – Order Dictyosiphonales – Family Punctariaceae
Thallus (sporophyte) complanate, solid, simple or occasionally lacerate, thin, membranous, usually 5–30 cm long and 2–8 cm broad, ovate to ligulate with a cuneate base and small rhizoidal holdfast. Growth initially from a trichothallic apex, soon becoming diffuse. Structure (2–) 4–6 cells thick, the outer layer phaeoplastic and mostly similar in size to the inner cells; phaeoplasts numerous, each with a pyrenoid. Phaeophycean hairs scattered, single or in small groups, on the surface or margin.
Microthallus streblonemoid, filamentous, branched.
Reproduction: Plurilocular sporangia scattered or clustered, developed from cortical cells, swollen and protruding slightly, with numerous locules. Unilocular sporangia scattered, transformed from cortical cells, swollen. Zooids from both types of sporangia reproducing the macrothallus directly or via the microthallus.
Life history usually direct from the sporophyte via the microthallus.
Lectotype species: P. plantaginea (Roth) Greville.
Taxonomic notes: A genus of 10–15 species, in temperate and cooler seas.
Punctaria is similar in form to Petalonia, but differs in having cortical and medullary cells of similar size, several phaeoplasts per cell, and in having the reproductive organs developed in single cells, not in extensive sori.
GREVILLE, R.K. (1830). Algae Britannicae. (Edinburgh.)
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
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State Herbarium of South Australia