†Pionoceras Ulrich et al. 1942 (mollusk)
Cephalopoda - Tarphycerida - Tarphyceratidae
Parent taxon: Tarphyceratidae according to C. Teichert et al. 1964
Sister taxa: Campbelloceras, Centrotarphyceras, Cycloplectoceras, Eurystomites, Moreauoceras, Pilotoceras, Seelyoceras, Tarphyceras
Subtaxa: Pionoceras pomponium, Pionoceras smithvillense, Pionoceras swartzi, Pionoceras vokesi
Ecology: fast-moving nektobenthic carnivore