Fig. 5 in Triassic coleoid beaks and other structures from the Calcareous Alps revisited

Fig. 5. The isolated upper beak and arm hooks of unknown coleoid (GM-P393) from the Buchenstein Formation, uppermost Anisian, Middle Triassic, Seceda Mountain, Gardena Valley, NE Italy. A1, an overview of the specimen; A2, enlarged arm hook; A3, the anterior part of the upper beak showing a pointed hook-shape rostrum and a deep U-shape inter-space between the lateral walls; A4, S-shape boundary between a rostrum and lateral wall. Abbreviations: ah, arm hook; bl, the curved broken lines consisted from the hook-like structures in the vicinity of the isolated upper beak from the NE Italy; lw, lateral wall of the upper beak; r, rostrum of the upper (dorsal) beak; sah, transversely sectioned arm hook; w, wing of the beak.