Parapuzosia seppenradensis

Parapuzosia seppenradensis is the largest known species of ammonite. It lived during the Lower Campanian Epoch of the Late Cretaceous period, in marine environments in what is now Westphalia, Germany. A specimen found in Germany in 1895 measures 1.8 m (5.9 ft) in diameter, although the living chamber is incomplete. It is estimated that if complete, this specimen would have had a diameter of approximately 2.55 m (8.4 ft) or even 3.5 m (11 ft). The total live mass has been estimated at 1,455 kg (3,208 lb), of which the shell would constitute 705 kg (1,554 lb).