Nuchalorgan

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As nuchal organ paired are sensory organs of the polychaete referred located in the head region and as a chemoreceptor act. These are fields of ciliated cells on the head flap or in the area of ​​the mouth segment, which are primarily responsible for the chemical testing of food ( sense of taste ).

Occurrence and training

Nuchal organ come exclusively with the Vielborstern (Polychaeta) within the annelid worms before (Annelida), but may be pronounced very differently there. In the former as a separate phylum be arranged spray worms (Sipuncula) they form ciliated areas in the mouth region between a circle of tentacles, the nerve connection directly from supraesophageal ganglion comes. In other polychaetes, the nuchal organs are mostly located as strongly ciliated structures on the posterior edge of the prostomium .

In the Amphinomida , the most famous representative of which is the fireworm ( Hermodice carunculata ), the nuchal organ (caruncle) forms a noticeable bulge on and behind the prostomium. In the Teuthidodrilus (known as "squidworm"), which were only discovered in 2010, the nuchal organs are formed as six pairs, which arise together with several very long tentacles on the head and are greatly elongated.

supporting documents

  1. ↑ Nuchal organs. In: Herder-Lexikon der Biologie. Spektrum Akademischer Verlag, Heidelberg 2003, ISBN 3-8274-0354-5 .
  2. ^ Günther Purschke : Sipuncula (Sipunculida), injection worms. In: W. Westheide, R. Rieger (Ed.): Special Zoology. Part 1: Protozoa and invertebrates. Gustav Fischer Verlag, Stuttgart / Jena 1997, pp. 332–333.
  3. ^ Wilfried Westheide : Annelida, annelid worms. In: W. Westheide, R. Rieger (Ed.): Special Zoology. Part 1: Protozoa and invertebrates. Gustav Fischer Verlag, Stuttgart / Jena 1997, pp. 358–359.
  4. ^ Wilfried Westheide: Amphinomida. In: W. Westheide, R. Rieger (Ed.): Special Zoology. Part 1: Protozoa and invertebrates. Gustav Fischer Verlag, Stuttgart / Jena 1997, p. 378.
  5. ↑ Karen J. Osborn, Laurence P. Madin, Greg W. Rouse: The remarkable squidworm is an example of discoveries that await in deep-pelagic habitats. In: Biology Letters. 7 (3), June 2011, pp. 449-453. doi: 10.1098 / rsbl.2010.0923 PMC 3097850 (free full text)