|A comparative study of Antithamnion tenuissimum and three varieties of A. cruciatum, including var. scandinavicum var. nov. (Rhodophyceae)|In: Nordic Journal of Botany. Oikos Editorial Office: Copenhagen. ISSN 0107-055X, more
Antithamnion cruciatum (C. Agardh) Nägeli var. scandinavicum var. nov. is described from material collected on the Danish and Swedish coasts. The variety was found growing on small stones, shells and on Zostera at depths between 0.5 to ca. 10m. A comparative study was made with var. cruciatum, var. radicans (J. Agardh) Collins et Hervey and Antithamnion tenuissimum (Hauck) Schiffner, including examination of type material and laboratory cultures of isolates from the Mediterranean and the Swedish west coast. Variety scandinavicum differs from the other varieties mainly by absence or rare development of gland cells, and sparsely branched whorl-branches. A. tenuissimum is distinguished from A. cruciatum by its shorter thallus, a sympodial type of branching, apparent absence of gland cells and adaxial-monostichous branchlets. Asexual reproduction was found to occur commonly in culture in the two species and their varieties, the morphology of which is discussed.