Jaekelopterus
Jaekelopterus is a genus of predatory eurypterid, a group of extinct aquatic arthropods. There are two known species: the type species J. rhenaniae from brackish to fresh water strata in the Rhineland, and J. howelli from estuarine stratum in Wyoming. Both species were first described as species of the closely related Pterygotus but were raised as a separate genus based...