Nannocalanus minor f. major   Sewell  (Copepod)
Organism information awaits expert curation
Class: Maxillopoda

Image copyright: Biotech books

a. The whole animal from the right side

Size (female): length 1.55-1.64 mm

The proportional lengths of the cephalothorax and abdomen are as 60 to 19; the abdomen is thus contained 3.2 times in the length of the anterior region of the body. The head and 1st thoracic segment are fused, but thoracic segments 4 and 5 are separate. The forehead is rounded and the posterior thoracic margin forms a uniform rounded curve.
The furcal ramus is 1.75 times as long as wide. The distal margin bears five setae, of which the 2nd is thickened and is at least twice as long as others. The 5th seta is small and is only one-half to one-third as long as the others. The 5th seta is small and is only one-half to one-third as long as setae 3 and 4. The distal seta is small and projects inwards in an S-shaped curve.
The genital aperture on the ventral face of the 1st abdominal segment is guarded by a semi-circular flap, that reaches across slightly more than four-fifths of the ventral aspect and is one and half times as wide from side to side as it is from before backwards. The first antenna reaches back to the hinder margin of the genital segment. Segments 1 and 2 are separate but segments 8 and 9 are fused. The 2nd antenna and the mouth-parts are of the usual calanoid type.
The first swimming leg has the usual structure, both exopod and endopod consisting of three segments. The endopod reaches to the levels of the 2nd inner seta on the margin of exopod 3. The 2nd swimming leg is , at any rate in certain individuals, characterized by the strong development of the marginal spines on exopod 1 and 2; the spine on exopod 1 reaches to the level of the junction of the third and fourth quarters of the external margin of exopod 2 and the spine on this latter segment may reach the level of the articulation of the proximal spine on exopod 3.

Synonym (s)

Common Name (s)
Economic Importance and Threats



• INDIA (Record: 1910-1925)

Literature Source(s)
  • Sewell, RBS (1999) The copepoda of Indian seas Biotech Books, Delhi, India 407 pp Available at - NIO, Goa
  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at -

Page last updated on:2009-07-24

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