Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 68. (Budapest 1976)

P. Komáromy, Zs.: Studies on terrestrial Chlorhormidium (Kütz.) Fott species (Ulotrichales)

ANNALES HISTORICONATURALES MUSEI NATIONALIS HUNGARICI Tomus 68. Budapest 1976. Studies on Terrestrial Chlorliormidium (Kütz.) Fott Species (Ulotrichales) by Zs. P.—KOMÁROMY, Budapest Abstract — Morphologically different developmental stages of Chlorhormidium species are distinguished under various names. Description of three new combinations and four were studied by phenological methods. The terrestrial G hlorhormidium species are associated with acid soils. With 5 figures. It is well known that different Chlorhormidium (KÜTZ.) FOTT species ( = Hormidium KÜTZ.) are wide-spread organisms in soil algal synusia (HAYTRÉN 1929, PETERSEN 1935, FEHÉR 1936, AKIYAMA 1966, MIXLIGER 1969). But we have no good key for determining terrestrial C'hlorhormidium species, since these species are inadequately understood, coupled with the fact that Odor hormidium is often confused with Ulothrix (BRAND 1913, GAY 1891, PETERSEN 1935). Based on some data from algological literature the examination in different ecosystems of PETERSEN (1915, 1928, 1932, 1935), FEHÉR (1936), REISIGE (1964), AKIYAMA (1966), AKIYAMA & NISHIGAMI (1967) and KOMÁROMY (1969) seems to prove that terrestrial G hlorhormidium species are associated with acid soils (Table 1.) Table 1. Occurrence of Chlorhormidium species at different pH values in nature author date pH value locality number of samples PETERSEN 1928 5.8—6.7 Denmark 15 PETERSEN 1932 5.9—6.7 Island 12 PETERSEN 1935 — Denmark 18 FEHÉR 1936 4.1—6.1 Europe N". and S. America — Australia REISIGL 1964 5.0—6,0 Austria 18 AKIYAMA 1967 3.6—6.5 Japan 17 MlLLIGER 1969 5.4—6.6 N. America 26 KOMÁROMY 1974 4.4—6.5 Hungary 33 The ontogenesis of algae is cyclic wherein we may distinguish morphologically different developmental stages. The weliknown stages of the species are generally confined to vegetative ones because they are most easily found. We can distinguish four developmental stages and within these a number of phenological phases of algae in analogy with vascular plants (resting, vegetative, reproductive, disorganization), by using the decimal descriptive method, elaborated by SZTJJKÓ-LACZA & FEKETE (1973). The developmental stages of algae however include different phenological phases and these do not agree with the phenological phenomena of vascular plants. Therefore, I give a special interpretation to the description of the developmental stages and phenophases of algae. The phenological phenomena is well distinguishable in the life cycle of some algal species. However, the phenologcial method is applicable in the cases of soil surface algal-colat only (Table 2.) When we have measured the length and width of many cells, collected at different localities, we have also used different culture media to distinguish different developmental stages, forms and physiological states of the species, by which we have a good key for determining GMorhormidium species. Ann. Hist.-nat. Mus. Nat. Hung., 1976, 68.