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Yelovichnus

Yelovichnus is an "enigmatic" genus known from fossils of the Ediacaran period. Yelovichnus was originally believed to be an ichnotaxon: its fossils, because of their "meandering nature", were initially thought to be feeding trails left by other life forms, such as annelids or mollusks. Better-preserved specimens later demonstrated that the fossils were not true feeding trails, as there was no evidence of turning by the life form that supposedly left them. The fossils are now recognized as belonging to an organism taking the form of "collapsed, segmented tubes", possibly an alga or a protist. It has also been argued that Yelovichnus and similar organisms are xenophyophores, large but single-cellular organisms that exist today in the abyssal zone. Due to similar structures found in their fossils, it is theorized that Yelovichnus may be related to Palaeopascichnus, as well as Aspidella and Neonereites. The main difference between Yelovichnus and Palaeopasicichnus is the shape of their segments: the segments of Yelovichnus took the shape of "closed, ovate-shaped loops", whereas the segments of Palaeopascichnus were quite varied in shape.

The genus and species was described by Mikhail A. Fedonkin in 1985 from the Ediacaran (Vendian) deposits of the White Sea area, Russia. Yelovichnus was named after the Yeloviy Creek near the locality.