PORT PHILLIP BAY


Southern Australian Krill 

Nyctiphanes australis Sars, 1883

View scientific description and taxonomy

Scientific Details

Carapace short, covering the head and all eight pairs of thoracic legs, exposing feathery thoracic gills; legs modified for swimming, each with two branches with long setae along each branch and a frilly gill near the base.

Source: Poore, G.C.B. (2004) Marine decapod Crustacea of southern Australia. A guide to identification (with chapter on Stomatopoda by Shane Ahyong). CSIRO Publishing, Melbourne, 574 pp.

Taxonomy

Phylum:
Arthropoda
Subphylum:
Crustacea
Class:
Malacostraca
Subclass:
Eumalacostraca
Superorder:
Eucarida
Order:
Euphausiacea
Family:
Euphausiidae
Genus:
Nyctiphanes
Species:
australis

General Description

Carapace covering the head and all thoracic legs. Eight pairs of thoracic legs modified for swimming, each has two branches with long setae (hairs) along each branch and a frilly gill near the base.

Biology

Krill are pelagic filter feeders on minute phytoplankton, zooplankton and detritus suspended in the water. The feeding mechanism of krill is a basket formed by the feathery thoracic legs, the inner margins of which are provided with long stiff hairs called setae. Krill usually occur in dense swarms and in Australian waters rafts of Nyctiphanes australis, covering several hectares, may occur at the surface where they are fed upon by muttonbirds (Sooty Shearwaters). Sometimes millions of krill are washed ashore on beaches where they die to form a silvery tidemark. Larger krill are the prime source of food for baleen whales like the Humpback.

Habitat

Pelagic to about 100 m depth.

Open water

Distribution guide

Southern temperate oceans, including New Zealand to Snares Islands and south-eastern Australia.

Species Group

Prawns, shrimps, lobsters Krill

Depth

Shallow (1-30 m)
Deep ( > 30 m)

Water Column

On or near sea floor Midwater

Max Size

Diet

Organic matter

Commercial Species

No

Global Dispersal

Recorded in Australia

Conservation Status

  • DSE Advisory List : Not listed
  • EPBC Act 1999 : Not listed
  • IUCN Red List : Not listed

Author

article author Taylor, J.

Dr. Jo Taylor is the Sciences Collections Online Coordinator at Museum Victoria.

Author

article author Poore, G.C.B.

Dr. Gary Poore is Principal Curator Emeritus at Museum Victoria.

citation

Cite this page as:
Taylor, J. & Poore, G.C.B., 2011, Southern Australian Krill, Nyctiphanes australis, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 18 Nov 2017, http://portphillipmarinelife.net.au:8098/species/5534

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