Symbiosis in brachiopods and brachiopod- attached trepostome bryozoans from the Katian of Estonia

Valves of the strophomenid brachiopod Sowerbyella tenera are often encrusted by trepostome bryozoan colonies in the lower Katian of Estonia. In some cases, the encrustation of Sowerbyella likely took place syn vivo. A single Sowerbyella tenera contains three Palaeosabella prisca borings that were bored post mortem into the interface between the encrusting trepostome colony and the ventral valve of Sowerbyella. The encrusting trepostome colonies contain a large bioclaustration in a tubular outgrowth of the bryozoan colony, Anoigmaichnus- like bioclaustrations, Kuckerichnus- like bioclaustrations, A. zapalskii, A. bretti, and a symbiotic conulariid. The bioclaustrated soft- bodied organisms and the conulariid colonized living bryozoans.

Automated summary

Valves of the Sowerbyella tenera brachiopod in lower Katian, Estonia, are often encrusted by trepostome bryozoan colonies. In some cases, the encrustation likely occurred while Sowerbyella was alive. A single Sowerbyella tenera specimen contains three post-mortem borings by Palaeosabella prisca, within the interface between the encrusting trepostome colony and the ventral valve. The encrusting trepostome colonies include Anoigmaichnus-like, Kuckerichnus-like bioclaustrations, A. zapalskii, A. bretti, and a symbiotic conulariid. The bioclaustrated organisms and the conulariid colonized living bryozoans.