Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 70. (Budapest 1978)

P. Komáromy, Zs.: Scotiella species (Chlorophyceae) and their theoretical life-cycle

ANNALES HISTORICO-NATURALES MUSEI NATIONALIS HUNGARICI Tomus 70. Budapest 1978. Scotiella Species (Chlorophyceae) and Their Theoretical Life-cycle by Zs. P.-KOMÁROMY, Budapest Abstract — During the floristical research in the Hortobágy National Park (HNP) a species was found and identified by the morphological features to be Scotiella levicostata HOLLERB. So far the Scotiella species were identified on the basis of morphological features of desorganizational and resting stages. Therefore, the descriptions include some hesitations, owing to the shape of chloroplast, the presence or absence of pyrenoid, the mode of reproduction, etc. The normal vegetative stages of some Scotiella species were described as Enallax. With 3 plates and 2 figures. I. Similarities and dissimilarities between Scotiella species In 1911 FRITSCH erected the genus Scotiella on the basis of two species, Scotiella antarctica and Sc. polyptera. Simultaneously, he had cleared the taxonomical position of Pteromonas nivalis CHOD. The most prominent morphological features of these Oocystoid green forms lie in the possession of longitudinal extensions of the cell wall, which run from one end of the cell to the other. The wings are placed more or less at equal distances round the circumference of the cell, so they have a characteristic stellata appearance in optical section. The cell content of Scotiella species is very difficult to investigate, i.e. the shape of the chloroplasts, the pyrenoid and the nucleus, because the whole of the protoplast usually is obscurring in coloured oil and fat. Later on, some other Scotiella species were described from snow (KOL 1968) and from different aerophytic biotopes (MANNAGETTA 1926; HOLLERBACH 1935; JAO 1947; BOURELLY 1951 ; GEITLER 1964 and REISIGL 1964), but the rank of the species characters was not widening. The different species separated from each other on the basis of the number and the trend of wings and by reason of cell content colour. If we compile a table which contains the most important morphological features of Scotiella species, we can draw some remarkable conclusions. According to Table 1, the first important fact is, that the shape and the number of chloroplasts are mostly uncertain (e.g. Sc. nivalis has a star-like chloroplast by CHODAT; according to WILLE this species has numerous parietal chloroplasts; and FRITSCH found an irregularly shaped, more or less central chloroplast with a pyrenoid in Sc. nivalis). These differences are well visible in the figures (Plate I: Figs. 1-9), and refer to that the chloroplasts of the examined members were in different stadia of desorganization. I observed in some other Chlorophyta species, e.g. Chlorhormidium flaccidum (KÜTZ) FOTT; Chi. crenulatum (KÜTZ.) KOM.; Stichococcus bacillaris NAG. and Chlorella vulgaris BEYER., that the chloroplasts were fragmented into pieces (or there was one chloroplast with blurred outline) in frozen soil samples. (Unpublished data.) According to SPRAY (1970) the size of the oil globules increases in Haematoeoccus when the tylakoids break down. Moreover, the same process was observed when the chloroplasts were transferred into chromoplasts (DODGE 1973). SZUJKÓ-LACZA et al. (1972) also examined the seasonal ultrastructural and physiological changes of chloroplasts in the shoots of Evonynius europeus L. It was demonstrated, that in winter time the chloroplasts were greenish-yellowish or dark green, the outlines could not be clearly seen in the chlorenchima of the shoot and some other structural changes were observed, too. Protuberances can often be found on the side of the thickened cell walls. Besides, an accumulation of starch and a chlorophyll content minimum were demonstrated. Ann. Hist.-nat. Mus. Nat. Hung., 70, 1978. 6 Természettudományi Múzeum Évkönyve 1978.