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Oithona plumifera

Baird (1843)

Download a fact sheet for Oithona plumifera (PDF 311KB)


Phylum Arthropoda
Subphylum Crustacea
Class Maxillopoda
Subclass Copepoda
Order Cyclopoida
Family Oithonidae
Genus Oithona
Species plumifera


  • Female: 1.11-1.51 mm

Distinguishing characteristics

  • Rostrum is distinctly pointed in dorsal view
  • Orange coloured plumes may be present
  • Tuft of hairs on anterior ventral surface of genital somite


  • Very difficult to identify


  • Plumes may be present
  • Anterior cephalosome is narrowed into pointed section
  • A1 long, reaches anal somite
  • Rostrum shape is distinctively pointed, rostrum visible in dorsal view
  • Proportional lengths of urosome somites and caudal ramus 10:28:15:16:16:15
  • Genital somite, twice as long as wide, swollen laterally on anterior third
  • Characteristic tuft of hairs on ventral side of genital somite
  • Caudal rami slightly shorter than anal somite
  • Can be confused with O. setigera, O. atlantica, O. longispina. Consider size, body form and the length of the distal outer marginal spine on P4 Re3




  • Nishida, S. (1985). "Taxonomy and distribution of the family Oithonidae (Copepoda, Cyclopoida) in the Pacific and Indian oceans." Bulletin of the Ocean Research Institute, University of Tokyo. Tokyo. no. 20: 1-167.