Children (26 direct children, 26 direct and indirect children):
Gastrioceras williamsi
Gastrioceras noduliferum
Gastrioceras multiseptum
Gastrioceras richthofeni
Gastrioceras melanesianum
Gastrioceras retiferum
Gastrioceras angusticameratum
Gastrioceras melvillensis
Gastrioceras listeri
Gastrioceras magoffinense
Gastrioceras adaense
Gastrioceras paucireticulatum
Gastrioceras jonesi
Gastrioceras marianum
Gastrioceras prone
Gastrioceras fittsi
Gastrioceras stenolobatum
Gastrioceras formosum
Gastrioceras liratum
Gastrioceras occidentale
Gastrioceras planorbiformis
Gastrioceras glenisteri
Gastrioceras montgomeryense
Gastrioceras pacificum
Gastrioceras tetragonum
Gastrioceras coronatum