Abstract
Cyclotella atomus collected from different rivers, reservoirs and lakes shows considerable morphological variability. On the basis of electronmicroscopic (EM) study, we propose Cyclotella atomus var. gracilis Genkal et Kiss as a new variety of this species.
Cyclotella atomus var. atomus has short and long radial striae, which are irregularly arranged on the same valve, and the alveolar chambers are not clearly divided from the central, hyaline part of the valve face. In addition to the described basic form, several specimens with other features have also been found and are thought to belong to an undescribed variety. The striae of the new variety are equal in length, and the alveolar chambers are clearly divided from the hyaline central area of the valve face by a curved structure.
There are EM micrographs on Cyclotella atomus var. gracilis under different names in different papers. The new variety has several characteristics also found in other species, e.g. Cyclotella caspia Grun., or C. meneghiniana Kütz.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Anonymous., 1975. Proposals for a standardization on diatom terminology and diagnoses. Nova Hedwigia, Beih. 53: 323–354.
Belcher, J. H. & E. M. F. Swale, 1978. Skeletonema potamos (Weber) Hasle and Cyclotella atomus Hustedt (Bacillariophyceae) in the plankton of rivers in England and France. Br. phycol. J. 13: 177–182.
Genkal, S. I., 1977. K metodike podschota nekotorih taksonomicheski znachimih strukturnih elementov stvorki u diatomovih vodoroslej sem. Thalassiosiraceae Lebour emend Hasle (Bacillariophyta). Bot. Zhurn. 62: 848–851.
Genkal, S. I., 1987. Morfologia I taxonomia nekotorih vidov diatomovih vodoroslej roda Cyclotella Kütz. Fauna i biologia presnovodnih organizmov. Nauka, Leningrad: 27–42.
Genkal, S. I., 1989. Quantitative estimation of diatom algae using the scanning and transmission electron microscopes. Diatom Res. 4: 249–254.
Genkal, S. I., 1990. Morfologia pantsirya centricheskih diatomej: aspekti sezonnoj izmenchivosti. In. V. Ekzeriev (ed.). Flora i produktivnost pelagitseski i litoralni fitocenozov vodoemov bassejna. Volgi. Nauka: 237–253.
Genkal, S. I. & L. Korneva, 1992. A simple method to assess the number of diatoms using TEM. Arch. Hydrobiol. 124: 357–366.
Genkal, S. I. & G. V. Kuzmin, 1979. O novih dlya flori SSSR predstavitelyah roda Cyclotella Kütz. (Bacillariophyta). Novosti Sistemat. Nizshih Rastenij. 16: 3–5.
Genkal, S. I. & I. V. Makarova, 1986. Novie dannie po morfologii pantsirya Cyclotella caspia (Bacillariophyta). Bot. Zhurn. 71: 371–374.
Genkal, S. I. & V. V. Odnopali, 1984. Novie dannie k flore diatomovih vodoroslej p. Selengi. Novisti Sistemat. Nizshih Rastenij. 21: 12–14.
Haste, G. R., 1962. Three Cyclotella species from marine localities studied in the light and electron microscopes. Nova Hedwigia 4: 299–307.
Helmcke, J. G. & W. Krieger, 1961. Diatomeenschalen in elektronmikroscopischen Bild III. Cramer, Weinheim.
Hustedt, F., 1937. Systematische und ökologische Untersuchungen über die Diatomeen-Flora von Java, Bali und Sumatra nach dem Material der Deutschen Limnologischen Sunda-Expedition. Arch. Hydrobiol., Suppl. 15: 131–506.
Hustedt, F., 1959. Die Diatomeenflora der Unterweser von der Lesummündung bis Bremerhaven mit Berücksichtigung des Unterlaufs der Hunte und Geeste. Veröff. Inst. Meersforsch. Bremerh. 6: 13–176.
Kiss, K. T., 1986. Species of the Thalassiosiraceae in the Budapest section of the Danube. Comparison of samples collected in 1956–63 and 1979–83. In Richard, M. (ed.) Proceedings of the 8th International Diatom Symposium, Koeltz, Koenigstein: 23–31.
Kiss, K. T., M. Coste, R. LeCohu & M. Nausch, 1988. Cyclotella caspia (Bacilllariophyceae) in some rivers and lakes in Europe (morphological observations). Cryptogamie, Algologie 9: 27–42.
Lowe, R. L., 1975. Comparative ultrastructure of the valves of some Cyclotella species (Baccillariophyceae). J. Phycol. 11: 415–424.
Lund, J. W. G., C. Kipling & E. D. Le Cren, 1958. The inverted microscope method of estimating algal numbers and the statistical basis of estimations by counting. Hydrobiologia 11: 143–170.
Nagumo, T. & H. Kobayasi, 1985. Fine structure of three freshwater and brackish water species of the genus Cyclotella (Bacillariophyceae) C. atomus, C. caspia and C. meduanae. Bull. Plankton Soc. Japan 32: 101–109.
Podani, J., 1988. Syn-Tax III. User's Manual. Abstr. Bot. Hung. 12: 1–183.
Proschkina-Lavrenko, A. I., 1959. De Cyclotella caspia Grunow. Not. Inst. Syst. Bot. Crypt. Acad. Sci. URSS 12: 69–75.
Ross, R., E. J. Cox, N. I. Karayeva, D. G. Mann, T. B. B. Paddock, R. Simonsen & P. A. Sims, 1979. An amended terminology for the siliceous component of the diatom cell. Nova Hedwigia Beih. 64: 513–533.
Schoeman, F. R. & R. E. M. Archibald, 1976. The diatom flora of Southern Africa, Part. I. Council for Scientific and Industrial Research, Pretoria.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Genkal, S.I., Kiss, K.T. Morphological variability of the diatom Cyclotella atomus Hustedt var. atomus and C. atomus var. gracilis var. nov.. Hydrobiologia 269, 39–47 (1993). https://doi.org/10.1007/BF00028002
Issue Date:
DOI: https://doi.org/10.1007/BF00028002