Department of Zoology at ANDC/Zoology Museum/Museum specimens/Annelida/Heteronereis

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Heteroneries

Date & Time : 23, November 2017 00:13


Heteronereis.jpg


Distribution:- free living worm found on surface of sea.

Habit and Habitat:- found in marine, swimming type habitat.

Identifying characters:-

Labelled diagram of HETERONEREIS.jpg
  • It is the sexual phase of Nereis.
  • Body:- differentiated into two distinct regions: an anterior atoke or non sexual region and a posterior epitoke or sexual region containing ova and sperms
  • Metamerism:- body consists of about 200 segments or metameres.
  • Head:- initial segments fused to form head consisting of eyes and peristomium.
  • Prostomium contains prostomial tentacles, ocelli and palps.
  • Parapodiacontain additional foliaceous lobes and setae become oar like.
  • Reduction of muscles and alimentary canal is observed due to development of gonads.