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Acartia (Acartia) negligens

Dana (1849)

Download a fact sheet for Acartia (Acartia) negligens (PDF 575KB)


Phylum Arthropoda
Subphylum Crustacea
Class Maxillopoda
Subclass Copepoda
Order Calanoida
Family Acartiidae
Genus Acartia (Acartia)
Species negligens


  • Female: 1.04 – 1.27 mm
  • Male: 0.8 - 1.02 mm

Distinguishing characteristics

  • Form of P5
  • Female with small spine on end of prosome
  • Male urosome hairy and with spinules


  • A1 shorter than body
  • Posterior prosome rounded with setae
  • The first 2 urosome somites hairy laterally, somites 2, 3, 4 and anal somite all with tiny spinules
  • Right P5 basipod 2 with rounded projection on internal border
  • Left P5 exopod 2 with 3 terminal spines and a plumose spine at mid length


  • A1 reaches to caudal rami, segment 1 with a small, slender spine
  • Posterior corner of prosome with one or many very small spines and a range of dorsal fine hairs
  • Outer distal plumose seta on P5, 5 times longer than terminal spine like segment which has coarse spinules for short distance at about mid length
  • Basis of P5 longer than wide, inner spine dentate
  • The first two segments of urosome with dorsal spinule on posterior border


  • One of two species of Acartia to primarily inhabit open ocean waters
  • Epipelagic, mesopelagic
  • Cosmopolitan
  • Restricted to between latitudes 40oS and 40oN


  • Eggs released into water
  • Omnivorous
  • Indicator species of Kuroshio Current in winter when NE monsoon prevails


  • Bradford-Grieve, J. M., (1999) The marine fauna of New Zealand: pelagic calanoid copepoda: Bathypontiidae, Arietellidae, Augaptilidae, Heterorhabdidae, Lucicutiidae, Metridinidae, Phyllopodidae, Centropagidae, Pseudodiaptomidae, Temoridae, Candaciidae, Pontellidae, Sulcanidae, Acartiidae, Tortanidae. National Institute of Water and Atmospheric Research, Wellington, New Zealand.
  • Greenwood, J. G. (1978). "Calanoid copepods of Moreton Bay (Queensland) 3. Families Temoridae to Tortanidae, excluding Pontellidae." Proceedings of the Royal Society of Queensland 89: 1-21.
  • Hsioa, S. H., Ka, S., Fang, T. H. & Hwang, J. S. 2011. Zooplankton assemblages as indicators of seasonal changes in water masses in the boundary waters between the East China Sea and the Taiwan Strait. Hydrobiologia, 666, 317-330.
  • Mauchline (1998). The biology of calanoid copepods.  Advances in Marine Biology Volume:33, Pages: i-x, 1-701.
  • Razouls C., de Bovée F., Kouwenberg J. et Desreumaux N., 2005-2009. - Diversity and Geographic Distribution of Marine Planktonic Copepods. Available at