Skip to main content

Fine structure of the spermatophore and intradermic penetration of sperm cells inMyzostoma cirriferum (Annelida, Myzostomida)

Summary

The spermatophore ofMyzostoma cirriferum is a white V-shaped structure up to ca. 500 μm long. It is formed by a translucent matrix which includes numerous cysts of two types that are very close together and tend to form interlacing twists. According to their contents, three spermatophoral regions can be distinguished: the body with the horns, the foot and the basal disc. The body-horns region forms the upper part of the spermatophore and extends over ca. 400 μm. This region includes mature spermiocysts which are formed by one cyst cell each including one to three groups of rolled up spermatozoons. Features of these cyst cells are their great length (up to 25 μm), their euchromatic nuclei each provided with a large nucleolus, their numerous mitochondria and osmiophilic vesicles included in the cytoplasm as well as cytoplasmic remnants of the residual bodies of the spermatids. Spermatozoons appear to be well adapted to the intradermic penetration occurring in this species in that all of them possess nuclei provided with dense nuclear grains, a hairpin-bent flagellum and a microtubular palissade. The spermatophore foot is located just below the body and extends over ca. 90 μm. It contains exclusively spermiocysts which include one to three abortive germinal cells. They differ also from the previous cysts by their smaller length (ca. 6–10 μm) and their more heterochromatic nuclei. The basal disc is the lower part of the spermatophore. It extends over ca. 10 μm and contains electron-dense vesicles in its upper part and vesicles with fibrillar material in its lower part. When mature myzostomids contact each other, a spermatophore is expulsed from one seminal vesicle of the donor myzostomid to the integument of the receiver myzostomid. The vesicles with fibrillar content are the first in contact with the cuticle of the receiver myzostomid. The material they include is supposed to have a histolytic action and to be responsible for the lysis of the cuticle and epidermal cells thus providing a passage for the spermatophore contents. Afterwards, cysts move as a result of the spermatozoons' beating and pass through the receiver's integument. At the time of penetration, cytoplasmic membranes of the cyst cells merge together forming an enormous syncytium extending into the whole receiver's body. This syncytium surrounds the spermatozoons and the abortive germinal cells. The whole process of intradermic penetration (i.e. from the fixation of the spermatophore to its reduction to an empty matrix) lasts from 1–5 h.

This is a preview of subscription content, access via your institution.

References

  • Afzelius BA (1983) The spermatozoon ofMyzostomum cirriferum (Annelida, Myzostomida). J Ultrastruct Res 83:58–68

    Google Scholar 

  • Afzelius BA (1984) Spermiogenesis inMyzostomum cirriferum (Annelida, Myzostomida). Vidensk Medd Dan Naturhist Foren Khobenhavn 145:11–21

    Google Scholar 

  • Aloia RC, Moretti RL (1973) Mating behavior and ultrastructural aspects of copulation in the rotiferAsplanchna brightwelli. Trans Am Microsc Soc 92:371–380

    Google Scholar 

  • Amin OM (1981) Leeches (Hirudinea) from Wisconsin, and a description of the spermatophore ofPlacobdella ornata. Trans Microsc Soc 100:42–51

    Google Scholar 

  • Anderson JM (1950) A cytological and cytochemical study of the testicular cyst cells in the Japanese beetle. Physiol Zool 23:308–316

    Google Scholar 

  • Apelt G (1969) Fortpflanzungsbiologie, Entwicklungszyklen und vergleichende Frühentwicklung acoeler Turbellarien. Mar Biol 4:267–325

    Google Scholar 

  • Beard J (1884) On the life history and development of the genusMyzostoma (F.S. Leuckart). Mitt Zool Stat Neapel 5:544–580

    Google Scholar 

  • Beard J (1898) The sexual condition ofMyzostoma glabrum (F.S. Leuckart). Mitt Zool Stat Neapel 13:293–324

    Google Scholar 

  • Carayon J (1974) Insémination traumatique hétérosexuelle chezXylocoris maculipennis (Hém. Anthocoridae). C R Acad Sci Paris 278 (D): 2803–2806

    Google Scholar 

  • Cuénot L (1949) Les Onychophores. In: Grassé P (ed) Traité de Zoologie, vol 6. Masson, Paris, pp 3–75

    Google Scholar 

  • Damas D (1969) Origine et structure du spermatophore deGlossiphonia complanata (L) (Hirudinée, Rhynchobdelle). Arch Zool Exp Gén 109:79–86

    Google Scholar 

  • Edwards JS (1961) On the reproduction ofPrionoplus reticularis (Coleoptera, Cerambycidae) with general remarks on reproduction in the Cerambycidae. J Microsc Sci 102:519–529

    Google Scholar 

  • Eeckhaut I (1989) Développement et reproduction deMyzostomum cirriferum (Leuckart) (Polychaeta, Myzostomidae). Master thesis, Université de Mons-Hainaut, Belgium

    Google Scholar 

  • Eeckhaut I, Lahaye MC, Jangoux M (1990) Postmetamorphic development ofMyzostomum cirriferum (Annelida) and effects of the symbiote on its crinoid host,Antedon bifida (Echinodermata). In: De Ridder C, Dubois P, Lahaye MC, Jangoux M (eds) Echinoderm research. Balkema, Rotterdam, pp 317–321

    Google Scholar 

  • Franzén A, Rice SA (1988) Spermatogenesis, male gametes and gametes interactions. In: Westheide W, Hermans CO (eds) The ultrastructure of polychaeta. Gustav Fischer, Stuttgart New York, pp 309–334

    Google Scholar 

  • Ganter P, Jollés G (1969–1970) Histochimie normale et pathologique, 2 vols. Gauthier-Villars, Paris, 1904 pp

    Google Scholar 

  • Harant H, Grassé P (1959) Classe des Annélides Achètes ou Hirudinées ou Sangsues. In: Grassé P (ed) Traité de Zoologie, vol 5. Masson, Paris, pp 471–593

    Google Scholar 

  • Jägersten G (1934) Studien über den histologischen Bau der männlichen Geschlechtsorgane und die Ausbildung des Spermiums beiMyzostomum. Zool Bidr Uppsala 15:1–22

    Google Scholar 

  • Jägersten G (1939) Über die Morphologie und Physiologie des Geschlechtsapparats und den Kopulationsmechanismus der Myzostomiden. Zpol Bidr Uppsala 18:163–242

    Google Scholar 

  • Jägersten G (1944) Über den Bau des Kopulationsapparates und Kopulationsmechanismus beiDinophilus. Zool Bidr Uppsala 22:61–86

    Google Scholar 

  • Jangoux M (1987) Diseases of Echinodermata. III. Agents metazoans (Annelida to Pisces). Dis Aquat Org 3:59–83

    Google Scholar 

  • Kato K (1952) On the development ofMyzostoma. Sci Rep Saitama Univ 1 (1):1–16

    Google Scholar 

  • Khoeler KJ, Birky CW (1966) An electron microscope study of the dimorphic spermatozoa ofAsplanchna (Rotifera). Z Zellforsch 70:303–321

    Google Scholar 

  • Mattei X, Marchand B (1987) Les spermatozoïdes des acanthocéphales et des myzostomides. Ressemblances et conséquences phylétiques. C R Acad Sci Paris 305:525–529

    Google Scholar 

  • Mattei X, Marchand B (1988) La spermiogénèse deMyzostomum sp. (Procoelomata, Myzostomida). J Ultrastruc Res 100:75–85

    Google Scholar 

  • Prenant M (1959) Classe des myzostomides. In: Grassé P (ed) Traité de Zoologie, vol 5 (1). Masson, Paris, pp 714–784

    Google Scholar 

  • Roosen-Runge EC (1977) The process of spermatogenesis in animals. Cambridge University Press, Cambridge, 214 pp

    Google Scholar 

  • Schroeder PC, Hermans CO (1975) Annelida: Polychaeta. In: Giese AC, Pearse JS (eds) Reproduction of marine invertebrates, 3, Annelids and echiurans. Academic Press, New York, pp 1–213

    Google Scholar 

  • Sterrer W (1974) Gnathostomulida. In: Giese AC, Pearse JS (eds) Reproduction of marine invertebrates, vol 1, Acoelomate and pseudocoelomate Metazoans. Academic Press, London, pp 345–357

    Google Scholar 

  • Stummer-Traunfels RR Von (1926) Myzostomida. In: Kükenthal W (ed) Handbuch der Zoologie 3. De Gruyter, Berlin, pp 132–210

    Google Scholar 

  • Westheide W (1984) The concept of reproduction in polychaetes with small body size: adaptations in interstitial species. In: Fischer A, Pfannenstiel HD (eds) Polychaete reproduction. Gustav Fischer, Stuttgart New York, pp 265–288

    Google Scholar 

  • Westheide W (1988) Genital organs. In: Westheide W, Hermans CO (eds) The ultrastructure of polychaeta. Gustav Fischer, Stuttgart New York, pp 263–280

    Google Scholar 

  • Wheeler WM (1896) The sexual phases ofMyzostoma. Mitt Zool Stat Neapel 12:227–302

    Google Scholar 

  • Wheeler WM (1898) The maturation, fecundation and early cleavage ofMyzostoma glabrum Leuckart. Arch Biol 15:1–77

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Eeckhaut, I., Jangoux, M. Fine structure of the spermatophore and intradermic penetration of sperm cells inMyzostoma cirriferum (Annelida, Myzostomida). Zoomorphology 111, 49–58 (1991). https://doi.org/10.1007/BF01632709

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01632709

Keywords

  • Seminal Vesicle
  • Cytoplasmic Membrane
  • Sperm Cell
  • Residual Body
  • Cyst Cell