Macrothrix (Crustacea) Movies

Macrothrix Video No. 1 - An up close and personal look at this translucent crustacean shows the intimate details of its inner life; under darkfield illumination at a magnification of 200x with a playing time of 18.8 seconds. Choose a playback format that matches your connection speed: 28.8k (modem), 56.6k (modem), or T1/Cable/DSL, or download this video clip in MPEG format (7.85 MB).

This cladoceran is one of many varieties of water flea and can be found along weedy margins of ponds and ditches. It has a discrete head, with antennae, and a bivalve shell that encloses all or most of the trunk and abdomen. Macrothrix filter-feeds on microscopic particles of organic matter by creating currents of water with its thoracic limbs.

Like other cladocerans, macrothrix are an important part of the food chain, filter-feeding on microscopic particles and phytoplankton and, in turn, providing food for juvenile fish. In the Great Lakes of North America, water fleas are the basic food for nearly all commercial fish species. Cladocerans are parthenogenetic most of the year, producing unfertilized eggs that, in turn, produce females.