Symbiotic endobiont biofacies in the Silurian of Baltica

The distribution of symbiotic endobionts in Silurian stromatoporoids of Estonia is correlated with the diverse sedimentary facies formed in this portion of the Baltica palaeocontinent. These depositional environments are characterized by different symbiotic endobiont associations. There are two onshore shallow water and one offshore deeper water symbiotic endobiont associations. Water depth was not the only controlling factor for their distribution: seawater nutrient levels, hydrodynamics (especially substrate stability), sedimentation rates and distribution of stromatoporoid hosts may have also played important roles.