Campylites

Campylites is a genus within the oppeliida subfamily Ochetoceratinae, equivalent to "Neoprionoceras" Spath 1928, that lived during the Oxfordian state at the beginning of the Late Jurassic.
"Campylites" differs from "Ochetoceras" in its narrower and more definitely tricarinate venter and in having more distinct primary ribs. It also lacks the mid lateral groove characteristic of "Ochetoceras".
References.
W.J. Arkell, et al., 1957. Mesozoic Ammonoidea, Treatise on Invertebrate Paleongology, Part L. Geological Society of America and University of Kansas Press.