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Paracalanus aculeatus

Giesbrecht (1888)

Download a fact sheet for Paracalanus aculeatus (PDF 315KB)


Phylum Arthropoda

Subphylum Crustacea

Class Maxillopoda

Subclass Copepoda

Order Calanoida

Family Paracalanidae

Genus Paracalanus

Species aculeatus


Female: 0.80-1.36 mm

Male: 0.92-1.36 mm

Distinguishing characteristics

Form of P5

Difficult to distinguish from P. campaneri and P. denudatus. Look at the shape of the seminal receptacle

More robust and bigger than P. indicus


A1 extends almost as far as caudal rami

Male P5 uniramous, asymmetrical, with 5 segments on left and 2 on right

Right P5 extending as far as proximal third of left leg segment 3

Can be confused with Arcocalanus due to small transparent swelling on the dorsal profile

Caudal rami as long as wide


A1 extends beyond caudal rami

Surface of B1 of swimming legs naked (inner edge may be feathered)

P4 exopod 2 has leaf like spines

P5 tiny, slender, short, uniramous, symmetrical, 2-segmented with 2 sub-equal terminal spines



Coastal and oceanic

Australian distribution includes North West Cape, Gulf of Carpentaria, Great Barrier Reef, Moreton Bay, Shark Bay and South East Australia including Tasmania

World distribution: cosmopolitan except for the Arctic and Antarctic oceans


Mean generation time from egg to adult 19.5 days at 28 °C

Growth rates and egg production appear to be food limited

Broadcast spawners

Slow, continuous swimmer that generates a feeding current to entrain potential food particles

Perceives food at a distance by chemoreception

Herbivorous filter feeder


Dakin, W. J. and Colefax A., (1940). "The plankton of the Australian coastal waters off New South Wales Part I." Publications of the University of Sydney: 210.

Bradford-Grieve, J. M. (1994). The marine fauna of New Zealand: Pelagic Copepoda: Megacalanidae, Calanidae, Paracalanidae, Mecynoceridae, Eucalanidae, Spinocalanidae, Clausocalanidae. National Institute of Water and Atmospheric Research, Wellington, New Zealand.

Razouls C., de Bovée F., Kouwenberg J. et Desreumaux N., 2005-2009. - Diversity and Geographic Distribution of Marine Planktonic Copepods. Available at[Accessed May 05, 2010].

Chisholm & Roff (1990)

Wiggert et al (2008)