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Doliolum nationalis

Borgert (1893)

Download a fact sheet for Doliolum nationalis (PDF 263KB)


Phylum Chordata
Class Thaliacea
Order Doliolida
Family Doliolidae
Genus Doliolum
Species nationalis


  • Gonozooid length up to 4 mm
  • Nurse length up to 2mm

Distinguishing characteristics

Gonozooid (Blastozooid)

  • Small, with a dextrally arched intestine
  • Anus is at the right side of the animal, at M6
  • Gill slits are attached dorsally behind M2, they extend backwards to M5 and turn slightly forward to the ventral attachment point just in front of M5
  • Endostyle begins frontal at M2 and extends to M4
  • Dorsal nerve ganglion is just in front of M4
  • Testis is variable in length, it extends horizontally on the left side of the animal (other doliolid species can have testes that are either oblique or spherical)
  • Differentiated from D. denticulatum by the length of the testes, the curved form of the gill slits and looking at where the gills end


  • Barrel shaped, without visceral mass, except for a heart
  • Budding on the dorso-ventral processs
  • M2-M8 fused in a continuous sheet
  • Nurses of Doliolum nationalis and Doliolum denticulatum cannot be separated


  • The distribution in Australian includes
  • Worldwide distribution North and Central Atlantic Ocean, Mediterranean Sea, Red Sea, subtropical SW Atlantic Ocean, tropical Indian and W Pacific Oceans



  • Boltovskoy, D. (Ed.) (2005). Zooplankton of South Atlantic, dvd ETI Bioinformatics.
  • Godeaux, J., Q. Bone and J.-C. Braconnot, 1998. Anatomy of Thaliacea. In: Q. Bone (ed.), 1998. The biology of pelagic tunicates. Oxford University Press, Oxford. pp 1-24.
  • Marine species identification portal,
  • van Couwelaar, M. (2003). Zooplankton and micronekton of the North Sea. Expert Center for Taxonomic Identification, Amsterdam.