Copepods

Two families

A superfamily of the Copepoda, featuring long antennules (20 or more segments) which reach well beyond the end of the metasome. The urosome is relatively small in proportion to total length, compared to other copepod superfamilies, and it narrows quickly from its broad attachment to the metasome.

In males the right antennule has a knee-like hinge about 1/4 the length from the tip, and the fifth legs are asymmetric.

There are two families.

CENTROPAGIDAE (Code OJ119999):

Fifth legs of males with the endopod either present or absent, the exopod 1-3 segmented. Fifth legs of females with the endopod 1-3 segmented, segment 2 of the exopod with a prominent spine or process at the medial distal corner.

This is a widespread family. Centropagidae occur in both fresh and brackish water and are particularly common in south-eastern Australia.

DIAPTOMIDAE (Code OJ129999):

Fifth legs of males with the endopod 1-segmented, the exopod 2 segmented and on the right modified as a moveable claw. Fifth legs of females with the endopod 1-2 segmented, the exopod 3-segmented, segment 2 with a medial distal clawlike projection.

Diaptomidae comprises two species of Diaptomus, which are confined to northern Australia. This is an entirely freshwater family. Habitats include lakes, ponds and ditches, whether permanent or temporary.

References:

Bayley, I.A.E. (1992) The non-marine Centropagidae (Copepoda: Calanoida) of the world. Guides to the Identification of the Microinvertebrates of the Continental Waters of the World. 1: 1-43. SPB Academic Publishers, The Hague.

Shiel, R.J. (1995) A Guide to Identification of Rotifers, Cladocerans and Copepods from Australian Inland Waters. Co-operative Research Centre for Freshwater Ecology Identification Guide No. 3., Albury, NSW.

Williams, W.D. (1980) Australian Freshwater Life: The Invertebrates of Australian Inland Waters.The Macmillan Company of Australia, Melbourne.