First description of rare Teichichnus burrows from carbonate rocks of the Lower Paleozoic of Estonia

Teichichnus burrows occur in the Sandbian, Katian and Telychian of Estonia associated with carbonate rocks. It is possible that Teichichnus is more common in the Sandbian than in the Lower to Middle Ordovician and in the Silurian. Two ichnospecies, T. rectus and T. patens, have been identified from the Lower Paleozoic of Estonia. This is the first record of T. patens in the Ordovician of Baltica. Teichichnus in the Sandbian, Katian and Telychian of Estonia is restricted to the shallowest tier levels. The rarity of Teichichnus in the carbonate sequences of the Ordovician and Silurian of Estonia reflects little bathymetric variability and an extremely low sedimentation rate in the shallow epicontinental basin.