Family ITIERIIDAE Cossmann, 1896 (Fig. 6 A-F)

Itieriidae Cossmann, 1896: 16 .

TYPE GENUS. — Itieria Matheron, 1842 (1842: 493) .

TYPE SPECIES. — Itieria cabanetiana d’Orbigny, 1841 (1841: 318) .

FAMILY CHARACTERS . — Shell oval to coniform, with high, narrow whorls. Spire short, irregularily coiled, depressed or convolute. Base umbilicate, with siphonal fasciole or short siphonal canal. Columella low, with one plait in Jurassic taxa, up to three in Cretaceous ones. Palatal wall with broad but low plait or pouch.

REMARKS

The whorls are high and narrow in cross section and reminiscent of the Acteonelloidea but possess a central cavity and a siphonal fasciole. In some cases only the internal mould of the cenrtral cavity is preserved (Fig. 6C). The Early Cretaceous Eotrochactaeon Akopjan, 1976 possesses a broad oviform shell with a short spire and 3 columellar plaits and is externally homologous with the Acteonelloidea genus Trochactaeon Meek, 1863 (Fig. 6F).A siphonal fasciole recognizable in axial sections of the columella distinguishes Eotrochactaeon from this genus (see Kollmann 1982; Sohl & Kollmann 1985).