FIRST EVIDENCE OF COLOR PATTERNS ON CONCHS OF THE LOWER MOSCOVIAN (MIDDLE PENNSYLVANIAN) COILED NAUTILOIDS FROM THE DONETS BASIN, UKRAINE

New finds of well-preserved remains coiled nautiloids from lower Moscovian sediments (Kamenskaya Formation) the Donets Basin (eastern Ukraine) allowed to describe color pattern on conch surface species genera Parametacoceras, Metacoceras, Coelogasteroceras and Ephippioceras. The studied is represented by longitudinal light bands along ventrolateral shoulder (Parametacoceras Metacoceras), transverse thin lines venter (Ephippioceras), a black spot body chamber (Coelogasteroceras). Described patterns represent disruptive coloration. Environmental conditions, e.g. slow sedimentation, absence agents mechanical chemical destruction, dysaerobic conditions rapid burial were obviously most important factors for preservation coloration conchs nautiloids.