Affiliation:
1. Paleontological Institute of the Russian Academy of Sciences
2. Geological Institute RAS, Research Organization of the Russian Academy of Sciences
3. Dobretsov Geological Institute of Siberian Branch of Russian Academy of Sciences
Abstract
A new locality Kimiltei, Irkutsk region, where unmineralized remains of arthropods were buried en masse, is described. U-Pb zircon dating indicated the Cambrian age and gave the youngest values 491 ± 6 Ma. Arthropods in Kimiltey are represented by Chasmataspidida, Synziphosurina and Euthycarcinoidea. The last two groups have not been known on the Siberian platform, and the first one has been described here only from the Devonian rocks. The Irkutsk finds fall into the ranks of the most ancient representatives of their groups, and their ranges turned out to be wider than previously known. Attention was drawn to their co- burial as the representatives of these groups have never been found together before. Taking into account that the descendants of all three groups gave rise to terrestrial lines of chelicerates and insects, thus the Kimiltey assemblage is the entire fauna of the land arthropods ancestors. Their co-habitation indicates they started their expansion on land from some close ecological niches in the intertidal zone.
Publisher
The Russian Academy of Sciences
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