Bioclaustration in Devonian fenestrate bryozoans. The ichnogenus Caupokeras McKinney, 2009

The ichnogenus Caupokeras is the only reported case of bioclaustration in which an symbiont is enveloped by fenestrate bryozoans. In this paper, type and additional material of Caupokeras from Belgium, Germany and Spain is revised and the number of bryozoan genera on which it occurs is expanded; a possible case from the Carboniferous of the USA is discussed and an expanded description of the ichnogenus and a palaeobiological interpretation are provided. The association between the fenestrate bryozoans and the sclerobionts that gave rise to this trace seems to have been more advantageous for the latter.