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Subeucalanus crassus

Giesbrecht (1888)

Download a fact sheet for Subeucalanus crassus (PDF 815KB)


Phylum Arthropoda
Subphylum Crustacea
Class Maxillopoda
Subclass Copepoda
Order Calanoida
Family Subeucalanidae
Genus Subeucalanus
Species crassus


  • Female: 2.46 - 3.70 mm
  • Male: 2.40 - 3.10 mm

Distinguishing characteristics

  • Female with robust body and short, rounded anterior cephalosome


  • Does not have distinct secondary sexual features
  • P5 right absent
  • P5 left uniramous, 4 segmented with terminal spine
  • A1 reaches to end of caudal rami


  • Anterior cephalosome rounded and short
  • A1 reaches just beyond caudal rami
  • A2 endopod segment 1 shorter than endopod segment 2 and about 2times as long as wide
  • Basis of mandibular palp with 3 setae, endopod reaches the distal boarder of basis, endopod segment 1 with 2 setae, endopod segment 2 with 4 setae
  • Maxilla 1 inner lobe 3 with 4 setae, basis with 5 setae
  • Maxilliped endopod segments 1 and 2 with 4 setae each
  • Genital somite wider than long and ‘onion’ shaped
  • Caudal rami slightly asymmetrical
  • Anal somite fused with furca
  • Left second caudal rami setae longer than right




  • Bradford-Grieve J., (1994). The marine fauna of New Zealand: Pelagic calanoid copopoda: Megacalanidae, Calanidae, Paracalanidae, Mecynoceridae, Eucalanidae, Spinocalanidae, Clausocalanidae. New Zealand Oceanographic Memoir 102.
  • Conway DVP, White, R.G., Hugues-Dit-Ciles, J., Gallienne, C.P. and Robins, D.B. (2003). Guide to the coastal and surface zooplankton of the south-western Indian Ocean, Vol Occasional Publications No. 15. Marine Biological Association of the United Kingdom.