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Rounded phosphatic structures (H elements) of euconodonts and their function (Euconodontophylea)
G.I. Buryi & A.P. Kasatkina
Abstract. Morphological analysis is done of the rounded structures in the head part of euconodont imprints from the Carboniferous deposits of Granton (Scotland), and the Ordovician Soom Shale (South Africa) and the rounded phosphatic structures present separately in the Upper Silurian and Upper Devonian deposits of Germany and Lower Triassic deposits of Primorsk Terr. (Russia). The identity of these structures in morphology and ontogenetic stages testifies that all of them belong to euconodonts. The rounded head structures of euconodonts, or H elements (Buryi & Kasatkina, 2001), appear to be analogous to the skeletal attaching plates of Chaetognatha. They were arranged in pairs in the anterior part of head in front of the tooth apparatus symmetrically to the sagittal axis of the euconodont and their surface was completely coated with a soft connective-muscular tissue like a cap. The H skeletal elements are rather a part of the mouth assemblage of euconodont animals along with the pharynx, P, M, and S elements of the tooth apparatus, and muscles (connective-muscular tissue). The presence of skeletal attaching plates (H elements) in euconodonts is responsible for the unique structure of the head part and of the whole animal (the euconodont mouth is arranged along the sagittal axis between the H elements). This supports recognition of these animals as a separate type, Euconodontophylea (Kasatkina & Buryi, 1999).
Zoosystematica Rossica, 2003, 12(2): 157–161 ▪ Опубликовано в печати 20 мая 2004 г.
https://doi.org/10.31610/zsr/2003.12.2.157 ▪ Открыть полную статью 
Литература
Aldridge, R.J., Briggs, D.E.G., Smith, M.P., Clarkson, E.N.K. & Clark, N.D.L. 1993. The anatomy of conodonts. Phil. Trans. Roy. Soc., B340: 405-421. https://doi.org/10.1098/rstb.1993.0082
Aldridge, R.J. & Theron, J.N. 1993. Conodonts with preserved soft tissue from a new Ordovician Konservat-Lagerstätte. J. Micropalaeontol., 12: 113-117. https://doi.org/10.1144/jm.12.1.113
Briggs, D.E.G., Clarkson, E.N.K., Aldridge, R.J. 1983. The conodont animal. Lethaia, 16(1): 1-14. https://doi.org/10.1111/j.1502-3931.1983.tb01139.x
Buryi, G.I. & Kasatkina, A.P. 2001. Functional importance of new skeletal elements (“eye capsules”) of euconodonts. Albertiana, 26: 7-10.
Donoghue, P.E.J., Forey, P.L. & Aldridge, R.J. 2000. Conodont affinity and chordate phylogeny. Biol. Rev., 75: 191-251. https://doi.org/10.1017/S0006323199005472
Gabbott, S.E., Aldridge, R.J. & Theron, J. 1995. A giant conodont with preserved muscle tissue from the Upper Ordovician of South Africa. Nature (N.Y.), 374(6525): 800-803. https://doi.org/10.1038/374800a0
Kasatkina, A.P. 1982. Shchetinkochelyustnye morei SSSR i sopredel’nykh vod [Chaetognaths in the seas of the USSR and adjacent waters]. Leningrad: Nauka. 136 p. (In Russian).
Kasatkina, A.P. & Buryi, G.I. 1999. The position of the phyla Chaetognatha and Euconodontophylea in the classification of Metazoa. Zoosyst. Ross., 8(1): 21-26.
Müller, K.J., Nogami, Y. & Lenz, H. 1974. Phosphatische Ringe als Microfossilien im Altpaläozoikum. Palaeontographica (A), 146: 79-99.
