Zoomorphology

, Volume 116, Issue 3, pp 133–142 | Cite as

The nervous system ofNectonema munidae andGordius aquaticus, with implications for the ground pattern of the Nematomorpha

  • Andreas Schmidt-Rhaesa
Original Article

Abstract

The nervous system ofNectonema munida is shown to be composed of a brain, a ventral nerve cord with an anterior and a posterior enlargement, a dorsal nerve cord and a plexus-like basiepidermal nervous system. The ultrastructure of these parts is given. Additionally, the ventral nerve cord ofGordius aquaticus is ultrastructurally described. The results are compared with the literature to work out the ground pattern of the Nematomorpha according to the nervous system. This contains a circumpharyngeal brain with a main subpharyngeal portion and a weak suprapharyngeal portion, a ventral and dorsal intraepidermal nerve cord and a peripheral nervous system. The ground pattern of the nervous system of nematomorpha is then compared to that of other Nemathelminthes. The form of the brain and the distribution of perikarya are derived characters of the Nematomorpha. The existence of an unpaired ventral and an unpaired dorsal nerve cord and the position of these two cords in epidermal cords are synapomorphies of the Nematomorpha and the Nematoda.

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References

  1. Ahlrichs W (1995) Ultrastruktur und Phylogenie vonSeison nebaliae (Grube 1859) andSeison annulatus (Claus 1876). Cuvillier, GöttingenGoogle Scholar
  2. Bird AF, Bird J (1991) The structure of nematodes. Academic Press, San DiegoGoogle Scholar
  3. Bock S (1913) Zur Kenntnis vonNectonema und dessen systematischer Stellung. Zool Bidr Uppsala 2:2–28Google Scholar
  4. Bresciani J (1991) Nematomorpha. In: Harrison FW, Ruppert EE (eds) Microscopic anatomy of invertebrates, vol 4, aschelminthes. Wiley-Liss, New York, pp 197–218Google Scholar
  5. Bürger O (1891) Zur Kenntnis vonNectonema agile Verr. Zool Jahrb Anat 4:631–652Google Scholar
  6. Ehlers U, Ahlrichs W, Lemburg C, Schmidt-Rhaesa A (1996) Phylogenetic systematization of the Nemathelminthes (Aschelminthes). Verh Dtsch Zool Ges 89.1:8Google Scholar
  7. Feyel T (1936) Recherches histologiques surNectonema agile Verr. Etude de la forme parasitaire. Arch Anat Microsc 32:197–234Google Scholar
  8. Kristensen RM (1991) Loricifera. In: Harrison FW, Ruppert EE (eds) Microscopic anatomy of invertebrates, vol 4, aschelminthes. Wiley-Liss, New York, pp 351–375Google Scholar
  9. Kristensen RM, Higgins RP (1991) Kinorhyncha. In: Harrison FW, Ruppert EE (eds) Microscopic anatomy of invertebrates, vol 4, aschelminthes. Wiley-Liss, New York, pp 377–404Google Scholar
  10. Lanzavecchia G, de Eguileor M, Valvassori R, Scari G (1995) Body cavities of Nematomorpha. In: Lanzavecchia G, Valvassori R, Candia Carnevali MD (eds) Body cavities: function and phylogeny. Mucchi, Modena, pp 45–60Google Scholar
  11. Malakhov VV (1980) Cephalorhyncha, a new type of animal kingdom uniting Priapulida, Kinorhyncha, Gordiacea, and a system of aschelminthes worms [in Russian with English summary]. Zool Zh 59:485–499Google Scholar
  12. Malakhov VV (1994) Nematodes. Smithsonian Institution Press, Washington LondonGoogle Scholar
  13. Malakhov VV, Adrianov AB (1995) Cephalorhynchia—a new phylum of the animal kingdom. [in Russian with English summary]. KMK Scientific Press, MoscowGoogle Scholar
  14. May HG (1919) Contributions to the life histories ofGordius robustus Leidy andParagordius varius (Leidy). Ill Biol Monogr 5:1–119Google Scholar
  15. Meissner G (1856) Beiträge zur Anatomie und Physiologie der Gordiaceen. Z Wiss Zool 7:1–144Google Scholar
  16. Montgomery TH (1903) The adult organisation ofParagordius varius (Leidy). Zool Jb Anat Ontog 18:387–474Google Scholar
  17. Nielsen C (1995) Animal evolution. Oxford University PressGoogle Scholar
  18. Nierstrasz HF (1907) Die Nematomorpha der Siboga-Expedition. Siboga Exped 20:1–22Google Scholar
  19. Rauther M (1904) Das Cerebralganglion und die Leibeshöhle der Gordiiden. Zool Anz 27:606–614Google Scholar
  20. Rauther M (1904) Zur Kenntnis und Beurteilung vonNectonema. Zool Anz 43:561–576Google Scholar
  21. Ruppert EE (1991) Gastrotricha. In: Harrison FW, Ruppert EE (eds) Microscopic anatomy of invertebrates, vol 4, aschelminthes. Wiley-Liss, New York, pp 41–109Google Scholar
  22. Schmidt-Rhaesa A (1996a) Zur Morphologie, Biologie und Phylogenie der Nematomorpha. Untersuchungen anNectonema munidae andGordius aquaticus. Cuvillier, GöttingenGoogle Scholar
  23. Schmidt-Rhaesa A (1996b) Monophyly and systematic relationships of the Nematomorpha. Verh Dtsch Zool Ges 89.1:23Google Scholar
  24. Schmidt-Rhaesa A (1996c) Ultrastructure of the anterior end of three ontogenetical stages ofNectonema munidae (Nematomorpha). Acta Zool (in press)Google Scholar
  25. Storch V (1991) Priapulida. In: Harison FW, Ruppert EE (eds) Microscopic anatomy of invertebrates, vol 4, aschelminthes. Wiley-Liss, New York, pp 333–350Google Scholar
  26. Svabenik J (1909) Beiträge zur Anatomie und Histologie der Nematomorpha (Czech with German summary). Sitzungsber Ges Wiss Prag, Math Nat Classe: 1–64Google Scholar
  27. Vejdovsky F (1886) Zur Morphologie der Gordiiden. Z Wiss Zool 43:369–433Google Scholar
  28. Vejdovsky F (1894) Organogenie der Gordiiden. Z Wiss Zool 57:642–703Google Scholar
  29. Ward HB (1892) OnNectonema agile Verrill. Bull Mus Comp Zool Harvard 23:135–188Google Scholar
  30. Wiedermann A (1995) Zur Ultrastruktur des Nervensystems beiCephalodasys maximus (Macrodasyida, Gastrotricha). Microfauna Marina 10:173–233Google Scholar
  31. Wright KA (1991) Nematoda. In: Harrison FW, Ruppert EE (eds) Microscopic anatomy of invertebrates, vol 4, Aschelminthes. Wiley-Liss, New York, pp 111–195Google Scholar

Copyright information

© Springer-Verlag 1996

Authors and Affiliations

  • Andreas Schmidt-Rhaesa
    • 1
  1. 1.II. Zoologisches Institut und MuseumUniversität GöttingenGöttingenGermany

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