The picture shows a member of the extinct halecomorph family Caturidae, Caturus, from the Solnhofen Limestone (Late Jurassic) of southern Germany. The forked tail and streamlined shape show that Caturus was a fast swimmer, and probably a predator.
Get a good look at the skull of a bowfin, as brought to you by the Massachusetts Museum of Natural History. Anglers may be interested in "Let's Show Some Respect,", a factsheet put out by the Michigan department of Natural Resources, Fisheries Division, or "John A. Grindle, Fossil at Law" from The In-Fisherman.