Pill bugs, fish lice

Code OR129999

Free-swimming, flattened isopods which attack active prey such as fish. Commonly called 'fish-lice' (see also Branchiura, family Argulidae, and some Copepoda). The family is mostly marine but a few species are recorded from inland waters. One species is subterranean.

The body is pill-bug shaped, widest at about mid-thorax. There are five visible abdominal segments. The telson is broad and rounded with short, flat uropods forming a tail fan.

References:

Horwitz, P., Knott, B. and Williams, W.D. (1995) A Preliminary Key to the Malacostracan Families (Crustacea) found in Australian Inland Waters . Co-operative Research Centre for Freshwater Ecology Identification Guide No. 4., Albury, NSW.

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

Wilson, G. D. ('Buz'). 1999. Preliminary phylogeny of the Phreatoicidea. Webpage at