Electronic Flora of South Australia Genus Fact Sheet
Phylum Phaeophyta – Order Chordariales – Family Leathesiaceae
Thallus (0.5–) 2–10 mm across, hemispherical to globular, mucoid, epiphytic with the basal layer adherent to the host with no or only very slight penetration of the host surface. Basal layer of radiating filaments closely to loosely adherent to the host. Medulla extensive and forming the greater part of the thallus, of erect, branched, colourless cells, closely appressed but not anastomosing. Determinate cortical filaments densely associated in a distinct stratum embedded in mucilage, arising from upper medullary cells, 20–60 cells long, usually curved above, cells cylindrical to laterally inflated above, accompanied by phaeophycean hairs. Phaeoplasts numerous per cell, each with a pyrenoid.
Reproduction: Plurilocular sporangia borne on upper cortical cells, or laterally at base of cortical filaments, single or grouped, uniseriate, or laterally from upper cells of cortical filaments and then shorter and becoming biseriate. Unilocular sporangia borne laterally at base of cortical filaments, ovoid to pyriform.
Life history unknown.
Lectotype species: C. umbellata (C. Agardh) Kützing.
Taxonomic notes: Corynophlaea contains about 5 described species, with four in the North Atlantic and Mediterranean, one known from Australia and two from New Zealand. The second New Zealand species (C. longifila Lindauer et al. 1961, p. 218) is here not considered distinct from the Australasian C. cystophorae, and a further new species is described below.
Corynophlaea differs from Myriactula in forming well-defined, often globose, mucoid thalli (including the stratum of cortical filaments), larger than in Myriactula, and which are adherent to the host by a basal layer which does not penetrate the host surface to any significant extent. The medulla in Corynophlaea is more extensively developed and the cortical filaments form a compact layer, embedded in mucilage, through which the phaeophycean hairs penetrate.
The type species of Corynophlaea, C. umbellata, has considerably shorter cortical filaments (4–7 cells long), and they are not so distinctively curved above, than in the two southern Australian species. It does, however, have the cortical filaments forming a distinct, dense, stratum embedded in mucilage. While the cortical filaments of the type are similar in size to those of Leathesia, they do not have the distinctly inflated terminal cell of the latter genus, and the medullary filaments do not show the cell anastomoses characteristic of Leathesia.
KÜTZING, F.T. (1843). Phycologia generalis. (Leipzig.)
LINDAUER, V.W., CHAPMAN, V.J. & AIKEN, M. (1961). The marine algae of New Zealand. II. Phaeophyceae. Nova Hedwigia 3, 129–350, Plates 57–97.
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
KEY TO SPECIES OF CORYNOPHLAEA
1. Medulla of closely associated filaments of ovoid cells; plurilocular sporangia borne in branched clusters from upper medullary cells, filiform and uniseriate
1. Medulla of loosely associated filaments of cylindrical cells; plurilocular sporangia borne laterally from upper cells of determinate cortical filaments, short and becoming biseriate
State Herbarium of South Australia