Erythrodermis allenii Batters in the life history of Phyllophora traillii Holmes ex Batters (Phyllophoraceae, Rhodophyta)

Publisher Website
Google Scholar
Abstract
A subtidal population of the small crustose red alga Erythrodermis allenii Batters, the type species of Erythrodermis, has been studied at Strangford Lough, N. Ireland. From January to March, E. allenii bears small sori of intercalary chains of 3–8 regularly cruciate, spherical or ovoid tetrasporangia 6–10 μm in diameter. Fertile specimens can readily be distinguished from similar North Atlantic species by vegetative and reproductive anatomy. Cultured tetraspores of E. allenii grew into male and cystocarpic female plants of Phyllophora traillii Holmes ex Batters (Phyllophoraceae). P. traillii is characterized by small blade size and marginal sterile and reproductive bladelets. A haploid chromosome number of 23 was obtained in these blades; crustose plants derived from P. traillii carpospores were diploid, with 46 chromosomes. Reproductive morphology of P. traillii was similar to that reported in other species of the genus. This is the first demonstration of a heteromorphic life history in Phyllophora. Crustose plants that developed from carpospores of P. traillii from the same site failed to form tetrasporangia, and instead gave rise directly to narrow, much-branched diploid blades that have not yet reproduced and require further investigation.