First finding of euconodont animals (Euconodontophylea) imprints on the territory of Russia
G.I. Buryi, A.P. Kasatkina, A.V. Zhuravlev & P.P. Safronov
Abstract. The paper presents data on first in Russia imprints of problematic euconodont animals found in the Lower Carboniferous deposits of the Kozhim River of the Northern Urals. In a thin interlayer of black carbonaceous mudstone, the first complete imprint of a euconodont animal and separated dental elements: "Spathognathodus" crassidentatus Branson & Mehl, Polygnathodus communis Branson & Mehl, Bispathodus sp. was found. The imprint is a long (about 4.8 mm), narrow (0.3-0.4 mm), worm-shaped body, exposed on one side, on which one can see a head, a trunk, and a tail. Behind the tail of the first imprint, there is a head of another younger specimen whose trunk appears to curve and pass into other plane. The first imprint of the euconodont animal was studied using a scanning electron microscope ZEISS EVO 50XVP without spraying its surface. A complete image of the euconodont animal trunk was obtained with low magnification (50Ч). With magnifications of 120Ч to 10000Ч, numerous details of its structure are observed. Complete data on the outer morphology of euconodont animals were thus obtained for the first time. These data support the hypothesis that the euconodonts belong to a distinct group of organisms established earlier, the phylum Euconodontophylea Kasatkina & Buryi, 1997.
Key words: tooth and H attaching elements, Lower Carboniferous, Scotland, Upper Ordovician, South Africa, Silurian, North America, Northern Urals, internal and external structures, muscular fibers, myomers, fishes, lower chordates, jawless craniates, transversal segments, fibrous structure, chaetognaths, isolated group of organisms
Zoosystematica Rossica, 2010, 19(1): 147-153 ▪ Published in print 15 July 2010
https://doi.org/10.31610/zsr/2010.19.1.147 ▪ Open full article 
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