Calcification of the Charophyte Oosporangium

  • A. R. Leitch


The oosporangium is a unique and complex structure consisting of a central reproductive cell (the oospore) surrounded by vegetative cells. In the subfamily Chareae, six vegetative ensheathing cells (i.e. five spiral cells and one basal cell), completely surround the oospore and are in intimate contact with it. After fertilization, a thick multilayered wall, the compound oosporangial wall (COW) forms around the oospore. This wall is derived by the simultaneous deposition of three layers by the ensheathing cells and three layers by the oospore. A calcified layer is deposited onto the COW by the ensheathing cells. Calcification occurs outside the plasmalemma of each ensheathing cell but within the confines of the cell wall; this is ‘extracytoplasmic’ calcification. The ensheathing cells secrete an organic matrix that nucleates calcite development and is presumably involved in crystal shaping. The calcite crystals of Chara are tabular and arranged in stacks, forming columns (like gastropod shell). Columns of calcite are found in Lamprothamnium calcine, although no substructure to these columns has been resolved. The differences seen in the calcified layer of Chara and Lamprothamnium using light microscopy are largely a matter of perspective as to which is being seen, the columns of calcite or the organic matrix.


Organic Matrix Calcite Crystal Calcium Carbonate Precipitate Primary Wall Gastropod Shell 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Borowitzka MA (1982) Mechanisms in algal calcification. In: Round FE, Chapman B (eds) Progress in phycological research, vol 1. Elsevier Biomedical Press, Amsterdam New York, pp 137 – 177Google Scholar
  2. Bremer K, Wantorp HE (1981) A cladistic classification of green plants. N J Bot 5: 1 – 3CrossRefGoogle Scholar
  3. Daily FK (1975) A note concerning calcium carbonate deposits in Charophytes. Phycologia Ser 4,14: 331 – 332Google Scholar
  4. DeDeckker P, Geddles MC (1980) Seasonal fauna of ephemeral saline lakes near the Coorong Lagoon, South Australia. Aust J Mar Freshwater Res 31: 677–700Google Scholar
  5. Degens ET (1976) Molecular mechanisms of carbonate, phosphate and silica deposition in the living cell. Top Curr Chem 64: 1 – 112CrossRefGoogle Scholar
  6. Feist M, Grambast-Fessard N (1984) New Porocharaceae from the Bathonian of Europe: phylogeny and palaeoecology. Palaeontology Ser 2,27: 295 – 305Google Scholar
  7. Horn of Rantzien H (1956) Morphological terminology relating to female charophyte gametangia and fructifications. Bot Not Ser 2, 109: 212 – 259Google Scholar
  8. Leitch AR (1986) Studies on living and fossil charophyte oosporangia. PhD Thesis, Bristol Univ, pp 1 – 182Google Scholar
  9. Leitch AR (1989) Formation and ultrastructure of a complex, multilayered wall around the oospore of Chara and Lamprothamnium (Characeae) Br Phycol J 24: 229 – 236Google Scholar
  10. Mattox KR, Stewart KD (1984) Classification of the green algae. A concept based on comparative cytology. In: Ervine DEG, John DM (eds) Systematics of the green algae, vol 27. Academic Press, New York London, pp 29 – 72Google Scholar
  11. Neville AC (1986) The physics of helicoids. Multidirectional ‘plywood’ structures in biological systems. Phys Bull 37: 74 – 76Google Scholar
  12. Round FE (1984) The systematics of the Chlorophyta: an historic review leading to some modern concepts (taxonomy of the Chlrophyta III). In: Ervine DEG, John DM (eds) Systematics of the green algae, vol 27. Academic Press, New York London, pp 1 – 28Google Scholar
  13. Sawa T, Frame PW (1974) Comparative anatomy of Charophyta: 1. Oogonia and oospores of Tolypella — with special reference to the sterile oogonial cell. Bull Torrey Bot Club Ser 3, 101: 136 – 144CrossRefGoogle Scholar
  14. Simkiss K (1964) Variation in the crystalline form of calcium carbonate precipitated from artificial seawater. Nature (London) 201:492–493Google Scholar
  15. Simkiss K (1986) The process of biomineralization in lower plants and animals — an overview. In: Leadbeater BSC, Riding R (eds) Biomineralisation in lower plants and animals. Univ Press, Oxford, pp 19 – 37Google Scholar
  16. Soulié Märsche I (1979) Etude comparée de gyrogonites de Charophytes actuelles et fossiles et phylogénie des genres actuelles. PhD Thesis, Univ Montpellier, pp 1–320Google Scholar
  17. Spence DHN (1982) The zonation of plants in freshwater lakes. Adv Ecol Res 12: 37 – 125CrossRefGoogle Scholar
  18. Stross RG (1979) Density and boundary regulations of the Nitella meadow in Lake George, New York. Aquat Bot 6: 285 – 300CrossRefGoogle Scholar
  19. Sundaralingam VS (1954) The developmental morphology of Chara zeylanica Willd. J Indian Bot Soc 33: 272 – 297Google Scholar
  20. Sundaralingam VS (1962) Studies on Indian Charophytes 1. Lychnothamnus. Proc Indian Acad Sci Ser B 55: 131 – 151Google Scholar
  21. Wilbur KM, Bernhardt AM (1982) Mineralization of Molluscan shell: Effect of free polyaminoacids on crystal growth rate in vitro. Am Zool 22: 952Google Scholar
  22. Wilbur KM, Saleuddin ASM (1983) Shell formation in the Mollusca. In: Saleuddin ASM, Wilbur KM (eds) Mollusca, Physiology, pt 1, vol 4. Academic Press, New York London, pp 523Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • A. R. Leitch
    • 1
  1. 1.J.I. Centre for Plant Science ResearchColney Lane, NorwichEngland

Personalised recommendations