Cephalopoda - Phylloceratida - Phylloceratidae
Alternative spelling: Geyeroceras
Parent taxon: Phylloceras according to W. J. Kennedy and H.C. Klinger 1977
See also Sepkoski 2002
Sister taxa: Phylloceras (Gyrophylloceras), Phylloceras (Hypophylloceras), Phylloceras (Phylloceras), Phylloceras (Triphyllites), Phylloceras album, Phylloceras asperaense, Phylloceras bakeri, Phylloceras burckhardti, Phylloceras contrarium, Phylloceras cylindricoides, Phylloceras doderleinianum, Phylloceras duodecimsulcatum, Phylloceras empedoclis, Phylloceras gargantuum, Phylloceras glennense, Phylloceras guettardi, Phylloceras haloricum, Phylloceras hebertinum, Phylloceras hebertinus, Phylloceras heterophyllum, Phylloceras insulare, Phylloceras isotypum, Phylloceras knoxvillense, Phylloceras kudernatschi, Phylloceras kunthi, Phylloceras lipoldi, Phylloceras lodaiense, Phylloceras meneghinii, Phylloceras micipsa, Phylloceras nilsoni, Phylloceras occiduale, Phylloceras persanense, Phylloceras psilomorphum, Phylloceras rouyanum, Phylloceras saxonicum, Phylloceras semistriatum, Phylloceras semisulcatum, Phylloceras seresitense, Phylloceras serum, Phylloceras shastalense, Phylloceras subplicatius, Phylloceras supraliasicum, Phylloceras timothyi, Phylloceras trifoliatum, Phylloceras vicarum
Subtaxa: Geyeroceras cylindricum Geyeroceras leptophyllum Geyeroceras subcylindricum
Distribution: