Cercopagis (upper) and Bythotrephes. Invading predatory cercopagids that have invaded the Great Lakes in ballast water. Bythotrephes invaded Lake Michigan in 1986. Cercopagis invaded lake Ontario and Lake Michigan in 1999. Arrows point to the thoracopods (feeding appendages). Microphotograph taken by J. Liebig, NOAA GLERL, 2001.
Spiny Water Flea Photo Credit usfoundation.net
