Dart formation in nematocysts of the sea anemone Metridium senile (Linnaeus, 1761) (Cnidaria: Anthozoa)


  • Carina Östman Animal Development and Genetics, Evolutionary Biology Centre (EBC), Uppsala University
  • Jens Roat Kultima Uppsala University
  • Sau Yu Grace Wong School of Animal and Microbial Sciences, University of Reading




nematocysts, cnidae, sea anemones, darts, SEM


In examining large acontia b-mastigophore and p-amastigophore nematocysts of the sea anemone Metridium senile (Linnaeus, 1761) darts were observed by interference-contrast light microscopy (LM) and scanning electron microscopy (SEM). The darts consist of closely packed spines detached from the shafts, still in three helical rows. Their spines form a hollow cylinder with a sharp tip and indented base, its width similar to that of an undischarged shaft but varying in length. b-mastigophore darts were more common than those of p-mastigophores and many were longer.


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How to Cite

Östman C, Roat Kultima J, Grace Wong SY. Dart formation in nematocysts of the sea anemone Metridium senile (Linnaeus, 1761) (Cnidaria: Anthozoa). scimar [Internet]. 2010Sep.30 [cited 2023Feb.2];74(3):499-510. Available from: https://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/1178