Cephalopoda - Ammonoidea - Nostoceratidae

Alternative combination: Helicoceras tenuicostatus

Belongs to Didymoceras according to W. J. Kennedy et al. 2000

Sister taxa: Didymoceras angulatum, Didymoceras binodosum, Didymoceras californicum, Didymoceras cheyenense, Didymoceras cheyennense, Didymoceras cochleatus, Didymoceras hornbyense, Didymoceras navarroensis, Didymoceras nebrascense, Didymoceras newtoni, Didymoceras nicolletii, Didymoceras platycostatum, Didymoceras stevensoni, Didymoceras subtuberculatum, Didymoceras tortus, Didymoceras tricostatus, Didymoceras umbilicatus, Didymoceras uncus, Didymoceras vespertinus

Ecology: fast-moving nektonic carnivore