Microorganisms on Crossopterygians scale of the Carboniferous age, “Emyaksin-Khayata” place (Yakutia, Viluy river)

Abstract

In the Emyaksinskaya formation of the Lower Carboniferous, exposed on the Viluy river, there is a fish occurrence known as “Emyaksin-Khayata”. Teeth, scales and bones of fossil fish were found in slightly compacted sandstones. Fossil parasites, represented by unicellular mucous microorganisms, were found on one of the scales of Crossopterygians by the author for the first time, as a result of the studies carried out using Jeol JSM–6480LV scanning microscope. In the Emyaksin-Khayata place, the relationship between fish and microorganisms was antagonistic. Microorganisms used the fish surface, places between tubercles, as a habitat, and possibly as a source of organic matter. Parasite settlement between scale tubercles, in the outer layer of the Crossopterygians skin, could cause occlusion of epidermis pores, blood supply disturbance, and the death of this fish. Along with natural-climatic and other habitat factors, parasite settlements on fish scales could be one of the possible reasons of their death and the formation of the “Emyaksin-Khayata” taphozonose. This place is subject to protection as a site of special scientific-educational interest.