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Phosphatic spicules in the nematocyst batteries of Nanomia cara (Hydrozoa, Siphonophora)

Summary

The complex, erupting nematocyst batteries of Nanomia cara are described. In addition to the cnidoband, the battery has a central axis containing longitudinal muscles and nerves that run right through to the terminal filament. In addition, an elastic strand lies coiled within the battery. After eruption of the battery, this strand keeps the prey attached to the tentacle. The strand bears hook-like spicules, equipped with barbs that project beyond the surface. Electron microscopy shows that the elastic strand is a mesogloeal structure tunnelled through and through with cellular processes deriving from both ectoderm and endoderm and that the spicules lie in cellular pockets in the interior of the elastic strand. There is nothing in the structure of the spicules or their cellular sheaths to suggest an origin from nematocysts. Energy dispersive X-ray microanalysis shows strong peaks for calcium and for phosphorus in the spicules, indicating that the mineral present in them is an apatite. An organic matrix is also found in the form of fine filaments and a granular axial structure. The spicules are arranged in a linear series along the elastic strand showing progressive increase in size and structural elaboration.

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References

  1. Bedot M (1888) Sur l'Agalma Clausi n. sp. Rev Suisse Zool 5:73–91

    Google Scholar 

  2. Chun C (1891) Die Canarischen Siphonophoren I. Stephanophyes superba und die Familie der Stephanophyiden. Abh Senkenb Naturforsch Ges 26:1–75

    Google Scholar 

  3. Claus C (1860) Über Physophora hydrostatica nebst Bemerkungen über andere Siphonophoren. Zeit Wiss Zool 10:295–332

    Google Scholar 

  4. Claus C (1878) Über Halistemma tergestinum n. sp. nebst Bemerkungen über den feinern Bau der Physophoriden. Arb Inst Zool Wien 1:1–56

    Google Scholar 

  5. Dietrich HF, Fontaine AR (1975) A decalcification method for ultrastructure of echinoderm tissues. Stain Tech 50:351–353

    Google Scholar 

  6. Grimmelikhuijzen CJP, Spencer AN, Carré C (1986) Organization of the nervous system of physonectid siphonophores. Cell Tiss Res 246:463–479

    Google Scholar 

  7. Huxley TH (1859) The oceanic hydrozoa. Ray Society, London, pp 1–143

    Google Scholar 

  8. Keferstein W, Ehlers E (1861) Zoologische Beiträge gesammelt im Winter 1859/60 in Neapel und Messina 1. Beobachtungen über die Siphonophoren von Neapel und Messina. Engelmann, Leipzig, pp 1–34

    Google Scholar 

  9. Kemp NE (1984) Organic matrices and mineral crystallites in vertebrate scales, teeth and skeletons. Am Zool 24:965–976

    Google Scholar 

  10. Kölliker A (1853) Die Schwimmpolypen oder Siphonophoren von Messina. Engelmann, Leipzig, pp 1–96

    Google Scholar 

  11. Korotneff A (1884) Zur Histologie der Siphonophoren. Mitth Zool Sta Neapel 5:229–288

    Google Scholar 

  12. Leuckart R (1853) Zoologische Untersuchungen I. Siphonophoren. Ricker, Gießen, pp 1–95

    Google Scholar 

  13. Leuckart R (1854) Zur nähern Kenntnis der Siphonophoren von Nizza. Arch Naturgesch Jahrg 20:249–377

    Google Scholar 

  14. Mackie GO (1973) Report on giant nerve fibres in Nanomia. Publ Seto Mar Lab 20:745–756

    Google Scholar 

  15. Mackie GO, Boag DA (1963) Fishing, feeding and digestion in siphonophores. Pubbl Stm Zool Napoli 33:178–196

    Google Scholar 

  16. Pautard FGE (1961) Calcium, phosphorus and the origin of backbones. New Scientist 12:346–366

    Google Scholar 

  17. Purcell JE (1984) The functions of nematocysts in prey capture by epipelagic siphonophores (Coelenterata, Hydrozoa). Biol Bull 166:310–327

    Google Scholar 

  18. Sars M (1846) Fauna littoralis Norvegiae, oder Beschreibung und Abbildungen neuer oder wenig bekannter Seethiere, nebst Beobachtungen über die Organisation, Lebensweise und Entwikkelung derselben. Dahl, Christiania, pp 1–94

    Google Scholar 

  19. Schneider KC (1899) Mitteilungen über Siphonophoren. IV. Nesselknöpfe. Arb Inst Zool Wien 11:1–52

    Google Scholar 

  20. Spurr AR (1969) A low-viscosity epoxy resin embedding medium for electron microcopy. J Ultrastruct Res 26:31–43

    Google Scholar 

  21. Totton AK (1965) A Synopsis of the Siphonophora. British Museum, London, pp 1–230

    Google Scholar 

  22. Vogt C (1854) Sur les siphonophores de la mer de Nice. Mém Inst Nat Genèv 1:1–164

    Google Scholar 

  23. Watabe N, Dunkelberger DG (1979) Ultrastructural studies on calcification in various organisms. Scanning Electron Microscopy 2:403–416

    Google Scholar 

  24. Watabe N, Pan Chi-Miau (1984) Phosphatic shell formation in atremate brachipods. Am Zool 24:977–985

    Google Scholar 

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Correspondence to G. O. Mackie.

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Mackie, G.O., Marx, R.M. Phosphatic spicules in the nematocyst batteries of Nanomia cara (Hydrozoa, Siphonophora). Zoomorphology 108, 85–91 (1988). https://doi.org/10.1007/BF00539784

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Keywords

  • Phosphorus
  • Apatite
  • Developmental Biology
  • Energy Dispersive
  • Progressive Increase