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Dolomedes is in the family Pisauridae, the fishing and nursery-web spiders. They are called fishing spiders because they have been known to capture and eat small fish, but most pisaurids eat mainly invertebrate prey. They are called nursery-web spiders because they do not spin a typical ensnaring spider web. The female carry the fertilized eggs and developing young spiderlings in an egg case held by her fangs, the chelicerae, (see photo specimen). Before the young start escaping from the egg case, the female attaches the case to usually terrestrial vegetation and spin a web around the case, the so-called nursery web. Adult female Dolomedes can have a leg spread of about 50 to 60 mm and are about a third larger than adult males. Both females and males are found on aquatic plants near the shore of standing and running water. How do they move across the water? Dolomedes triton specimens row across the water using four legs, gallop across the water using six legs, and sail across the water by taking advantage of wind currents and the spider's seemingly frictionless interaction with the surface of the water.* *Robert B. Suter (Vassar College). Locomotion on the water surface - gaits and modes. online at . A Quick Time movie showing rowing can be viewed from this site (2002). Photograph: Randy Mandryk (Source: University of Alberta BioDiTRL online database, accessed Dec. 7, 2015. Copyright restrictions apply.)