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P. KARPINSKY AND RESEARCH ON HELICOPRIONID FISHES, ENIGMATIC PALEOZOIC CHONDRICHTHYANS. ON THE 175TH ANNIVERSARY OF THE SCIENTIST’S BIRTH

December 2021 marks the 175th anniversary of Academician Aleksandr Petrovich Karpinsky (1846(7)-1936), an outstanding Russian naturalist, President of the USSR Academy of Sciences. He made a great contribution to the development of geology and paleontology in our country and laid the foundation of the doctrine of platforms. Having studied and described unusual remains from the Lower Permian of Ural Mountains-helicoprion (Helicoprion bessonowi), Karpinsky opened one of the most interesting pages in paleoichthyology. The discovery of the spiral apparatus caused a violent reaction and discussions about its anatomical position among paleontologists all over the world. A. P. Karpinsky supported the opinion that this spiral-tooth whorl was situated in the rostral part of the cartilaginous skull. It was anteriorly protruded and dorsally coiled. He posited a separate family, Helicoprionidae, which includes chondrichthyans with spiral-tooth whorls. At present, the helicoprion is among the “hallmarks” of the Permian period. Its tooth whorls are demonstrated in the paleontological expositions of many museums. The article gives the history of some museum exhibits related to the helicoprionids, together with brief biographical data on A. P. Karpinsky.