Fig. 48 in Early-Middle Ordovician cephalopods from Ny Friesland, Spitsbergen - a pelagic fauna with Laurentian affinities

Fig. 48. Trocholitoceras juvenicostatum Ulrich, Foerste, Miller & Furnish, 1942, from bed PO 131, Olenidsletta Member, Floian, Ordovician, Profilstranda section, Ny Friesland, Spitsbergen. A–B. Specimen FMNH-P30323. A. Adoral view with siphuncular perforation preserved. B. Lateral view of fragment of body chamber with outer shell and ornamentation partly preserved. C. Specimen FMNH-P30330, lateral view with distinctive ribs. Scale bar = 20 mm for all figures.