| Popis: |
From research undertaken on brachiopods encrusted by auloporids at two intervals in the Frasnian (Beaulieu and Ferques Formations) of Boulonnais (France), we conclude that the most important factors influencing encrustation were usually (in decreasing order): size of the host, morphology, feeding currents, shell orientation in vivo and shell ornament. Shell structure (punctate or impunctate) seems not to have influenced the rate of encrustation. In the cases discussed, most but not all auloporids encrusted their hosts in vivo. The most favourable environments for development of both brachiopods and epibionts seem to have been hard bottoms and thin limestone beds alternating with argillaceous beds. The influence of environmental (sedimentologic) conditions is difficult to precisely specify in terms of the development of encrustation, but seems to have played an important role. |
