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Co jadły polskie dinozaury?

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Gardineria - a scleractinian living fossil

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The basic architecture (Bauplan) and microstructure of the skeleton of Recent Gardineria are noticeably different from those of most other modern scleractinians. The wall of the Gardineria skeleton is entirely epithecate (non-trabecular), while in the majority of modern Scleractinia the epitheca is either absent or added to the main wall which usually is of trabecular nature. These different patterns of theca formation reflect significant anatomical differences in the peripheral parts of the polyp. The Bauplan of Gardineria pattern, exceptional in the modern scleractinian fauna, was widespread among early Mesozoic corals, particularly among the Triassic protoheterastraeids. Similar skeletons also occur in some late Palaeozoic rugosans (e.g., polycoeliids). Zardinophyllum zardini, an aberrant Triassic scleractinian coral, with a supposed rugosan septal insertion, supports the hypothesis of the rugosan origin of the Scleractinia
The orbital wall in Nemegtbaatar gohiensis and Chulsanbaatar vulgaris, from the Late Cretaceous of the Gobi Desert, Mongolia, comprises a small lacrimal anteriorly, large orbital process of the frontal dorsally, orbitosphenoid posteriorly and maxilla ventrally. Nemegtbaatar also posesses an orbital process of the palatine ventrally, not recognized in Chulsanbaatar. Large frontal sinuses of both taxa are interpreted as related to lack of the sagittal crest. Other anatomical characters found in this study, such as orbital process of the frontal, ossified turbinals, ossified ethmoid and vomer, frontal, sphenoidal and maxillary sinuses, and the presence of the orbital process of palatine in Nemegtbaatar suggest a close relationship of multituberculates to monotremes and therian mammals. By the new data obtained from the serial sections the diagnostic character: orbital process of the palatine absent in Multituberculata, is no longer valid. Ossified ethmoid and maxillary turbinals, characteristic for Monotremata, Vincelestes, Marsupialia and Placentalia, are also present in Multituberculata. The precence of a cribiform plate and the precence of an ossified plate of ethmoid in Multituberculata is shared with Monotremata, Vincelestes, Marsupialia and Placentalia.
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Hartmaniellidae - living fossils among polychaetes

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The jaw apparatus of the Recent eunicoid polychaete Hartmaniella erecta is closely similar to those of the Mesozoic species of Palurites. It is concluded that the family Hartmaniellidae originated in the late Palaeozoic from an ancestor close to the Paulinitidae and is qlosely related to Kielanoprionidae. The lineage shows an extremaly slow rate of evolution. Hartmaniellids have been abundant during the whole Mesozoic while its Recent representation is only a relic. Palurites jurassicus sp. n. is proposed.
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The phylogenetics of potential Mesozoic ancestors of cuttlefish of a restricted order Sepiida von Zittel, 1895 (superorder Decabrachia Boettger, 1952) is reviewed. Microstructural studies of Mesozoic homeomorphs of cuttlebones (Pearceiteuthis gen. n., Loligosepia, Trachyteuthis, Actinosepia) are consistent with their assignement to the superorder Octobrachia Fioroni, 1981. The discovery of an embryonic Ceratisepia shell in the upper Maastrichtian of the Netherlands, indicates that true Sepiida did have a pre-Cenozoic origin. Cretaceous decabrachs of the order Spirulida Stolley, 1919 do not show evidence of the dorso-anterior shell growth vectors seen in Cenozoic spirulids, sepiids and octobrachs. Separate origins of the Sepiida and Spirulida within Cretaceous diplobelinid belemnites is still the most attractive hypothesis. Ceratisepia vanknippenbergi sp. n. from the upper Maastrichtian of the Netherlands and Pearceiteuthis buyi gen. et sp. n. from the Callovian of England are described.
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