Try Wilson, C.B. 1932. The copepods of the Woods Hole region, Massachusetts., U.S. Govt. Gosner is also useful as a quick reference Gosner, K L. 1979.
Nothing is really good for either meroplankton or mircos.
He does plankton in both offshore and estuarine areas. It has an most pointy head and a bluish tinge to the body. Gosner and Wilson both have good pics of it. Try Wilson, C.B. 1932. The copepods of the Woods Hole region, Massachusetts., U.S. Govt.