Belemnitellidae, Pavlow, 1914

Košťák, Martin & Wiese, Frank, 2008, Lower Turonian record of belemnite Praeactinocamax from NW Siberia and its palaeogeographic significance, Acta Palaeontologica Polonica 53 (4), pp. 669-678 : 671

Family Belemnitellidae, Pavlow, 1914 Genus Praeactinocamax Naidin, 1964

Type species: Belemnites plenus Blainville, 1827 , Upper Cenomanian (Late Cretaceous), England (see Blainville 1825 –27: 376, figs. 3, 11) .

Emended diagnosis.—Medium−sized to large belemnitellids (guard up to 115 mm long) with allometric growth; adult specimens stouter and more lanceolate in ventral view than juvenile specimens; usually with short cone−shaped alveolar fracture, but some species with very shallow pseudoalveolus; ventral fissure absent; ventral furrow and ventral notch sometimes present; juvenile guards long and slender (needle−shaped); adult guards predominantly lanceolate in dorsoventral view and subcylindrical in lateral view. Dorsolateral compressions and furrows usually present; striation and vascular imprints in some species; granulation rare (modified from Blainville 1825 –27; Christensen 1997a; Košťák 2004).