• Body and legs not covered with bivalve carapace
• Four pairs of stout legs are somewhat flattened, clearly segmented and prehensile
• Short body

• Polyphemus (and the family Polyphemidae) is represented by only one species in North America. It feeds almost exclusively as a predator on smaller zooplankton prey, especially rotifers (Packard 1992). Polyphemus is unusual as it is one of the few invertebrate predators in the plankton that feeds visually. It is often seen in dense swarms along the shore of lakes, moving out into the open water at night (Mattson 1979).

Mattson, M.T. 1979. Distribution patterns and population dynamics of Polyphemus pediculus (L.) (Crustacean, Cladocera) in a small New England lake. PhD. Dissertation. University of New Hampshire. Durham, NH. pp. 162.

Packard, A.T. 1992. Horizontal distribution, feeding rates and prey selectivity of the littoral predator Polyphemus pediculus. PhD. Dissertation. University of New Hampshire. Durham, NH. pp. 109.

• Polyphemus1.mov - Polyphemus in motion (501 KB).
• Polyphemus2.mov - Immature and adult Polyphemus swimming. Note the multidirectional swimming and the rapid movement of the second (swimming) antenna (2.2 MB).