Zeitschrift für Parasitenkunde

, Volume 71, Issue 6, pp 715–726 | Cite as

Ultrastructural observations of spore excystment, plasmodial development and sporoblast formation inHaplosporidium lusitanicum (Haplosporida, Haplosporidiidae)

  • C. Azevedo
  • L. Corral
  • F. O. Perkins
Original Investigations


The fine structure of spore excystment, plasmodial development, and sporoblast formation phases of the life cycle of the sporozoanHaplosporidium lusitanicum haplosporidian species recently described by Azevedo (1984), pathogenic to the plate limpetHelcion pellucidus (Gastropoda) is described. After liberation from the spore wall, the uninucleate amoebula penetrates the host and is first found in the connective tissue in contact with the periphery of the ovary and hepatopancreas. The amoebula develops into a plasmodium by enlargement and nuclear multiplication as evidenced by mitotic figures each consisting of a bundle of microtubules attached to spindle pole bodies situated in the nucleoplasm near the nuclear envelope. The cell becomes successively binucleated, tetranucleated, etc.. forming a multinucleated sporont containing several hundred nuclei. Each nucleus contains a nucleolus and obvious chromatin.

In the next phase a very irregular membranous system and some Golgi complexes begin to differentiate in the cytoplasm. Then, each nucleus and a portion of surrounding cytoplasm is encircled by a limiting membrane which arises from fusion of Golgi vesicles. In sporonts several hundred sporoblasts are thus formed.


Life Cycle Connective Tissue Fine Structure Plasmodium Formation Phase 
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. Azevedo C (1984) Ultrastructure of the spore ofHaplosporidium lusitanicum n. sp. (Haplosporida, Haplosporidiidae), parasite of a marine molluse. J Parasitol 70 (3):358–371Google Scholar
  2. Azevedo C, Coimbra A (1981) Nucleolar fine structure in oocytes ofHelcion pellucidus (Gastropoda, Prosobranchia). XVI Annual Meeting Port. Soc. E.M., Coimbra, PortugalGoogle Scholar
  3. Azevedo C, Corral L (1984) Some ultrastructural aspects of the life cycle ofHaplosporidium lusitanicum, with special reference to spore maturation. First Int. Coll Pathol Marine Aquaculture, Montpellier (France) p 34Google Scholar
  4. Ball SJ (1980) Fine structure of the spores ofMichinia chitonis (Lankester 1885) Labbé, 1896 (Sporozoa: Haplosporida) a parasite of the chiton,Lipidochitona cinereus. Parasitology 81:169–176Google Scholar
  5. Hillman RE, Maciolek NJ, Lahey JI, Belmore CI (1982) Effects of a Haplosporidian parasite,Haplosporidium sp., on Species of the molluscan woodborerTeredo in Barnegat bay, New Jersey. J Invert Pathol 40:307–319Google Scholar
  6. Jirovec O (1936)Haplosporidium cernosvitorovi n. sp. eine neue Haplosporidienart ausOpistocysta (Pristina)flagellum Leidy. Arch Protistenk 86:500–508Google Scholar
  7. Marchand J, Sprague V (1979) Ultrastructure deMinchinia cadomensis sp. n. (Haplosporida) parasite du décapodeRhithropanopeus harrisii tridentatus Maitland dans le Canal de Caen à la mer (Calvados, France). J Protozool 26:179–185Google Scholar
  8. Newman MW, Johnson CA, Pauley GB (1976) A Minchinia-like haplosporidian parasitizing blue crabs,Callinectes sapidus. J Invert Pathol 27:311–315Google Scholar
  9. Ormières R (1980)Haplosporidium parisi n. sp. haplosporidie parasite deSerpula vermicularis L. Étude ultrastructurale de la spore. Protistologica T. XVI (3):467–474Google Scholar
  10. Ormières R, de Puytorac P (1968) Ultrastructure des spores de l'Haplosporidium ascidiarum endoparasite du tunicierSydnium elegans Giard. CR Acad Sc (Paris) 266 (D):1134–1136Google Scholar
  11. Ormières R, Sprague V, Bartoli P (1973) Light and electron microscope study of a new species ofUrosporidium (Haplosporida), hyperparasite of Trematode sporocysts in the clamAbra ovata. J Invert Pathol 21:71–86Google Scholar
  12. Perkins FO (1968) Fine structure of the oyster pathogenMinchinia nelsoni (Haplosporida, Haplosporidiidae). J Invert Pathol 10:287–307Google Scholar
  13. Perkins FO (1969) Electron microscope studies of sporulation in the oyster pathogen,Minchinia costalis (Sporozoa: Haplosporida). J Parasitol 55:897–920Google Scholar
  14. Perkins FO (1971) Sporulation in the trematode hyperparasiteUrosporidium crescens De Turk, 1940 (Haplosporida: Haplosporidiidae) — An electron microscope study. J Parasitol 57:9–23Google Scholar
  15. Perkins FO (1975a) Fine structure ofMinchinia sp. (Haplosporida) sporulation in the mud crab,Panopeus herbstii. Mar Fish Rev 37:46–60Google Scholar
  16. Perkins FO (1975b) Fine structure of the haplosporidan “Kernstab”, a persistent, intranuclear mitotic apparatus. J Cell Sci 18:327–346PubMedGoogle Scholar
  17. Perkins FO (1976) Ultrastructure of sporulation in the European Flat oyster pathogen,Marteilia refringens. Taxonomic implications. J Protozool 23:64–74Google Scholar
  18. Perkins FO, van Banning P (1981) Surface ultrastructure of spores in three genera of Balanosporida, particularly inMinchinia armoricana van Banning, 1977 — The taxonomic significance of spore wall ornamentation in the Balanosporida. J Parasitol 67:866–874Google Scholar
  19. Rosenfield A, Buchanan L, Chapman GB (1969) Comparison of the fine structure of spores of three species ofMinchinia (Haplosporida, Haplosporidiidae). J Parasitol 55:921–941Google Scholar
  20. Sprague V (1978) Comments on trends in research on parasitic diseases of shellfish and fish. Mar Fish Rev 40:26–30Google Scholar
  21. Sprague V (1979) Classification of the Haplosporidia. Mar Fish Rev 41:40–44Google Scholar
  22. Trager W (1974) Some aspects of intracellular parasitism. Intracellular protozoa enter host cells in subtle ways and escape the cell's digestive processes. Science 183:269–273PubMedGoogle Scholar
  23. van Banning P (1977)Minchinia armoricana sp. nov. (Haplosporida), a parasite of the european flat oyster,Ostrea edulis. J Invert Pathol 30:199–206Google Scholar
  24. van Banning P (1979) Haplosporidian diseases of imported oysters,Ostrea edulis, in Dutch estuaries. Mar Fish Rev 41:8–18Google Scholar

Copyright information

© Springer-Verlag 1985

Authors and Affiliations

  • C. Azevedo
    • 1
  • L. Corral
    • 1
  • F. O. Perkins
    • 2
  1. 1.Department of Cell Biology, Institute of Biomedical SciencesUniversity of OportoPortoPortugal
  2. 2.Virginia Institute of Marine ScienceCollege of William and MaryGloucester PointUSA

Personalised recommendations