ABSTRACT A new ichnospecies, Caupokeras badalloi, is here erected from the Emsian (Lower Devonian) Aguión Formation of Asturias, NW Spain. It is a bioclaustration structure produced by the host-specific symbiotic intergrowth of two host bryozoan species, Leioclema elegans and Loxophragma cf. leptum, and a soft-bodied modular symbiont, possibly a hydroid. The distinctiveness of this bioclaustration structure creates the need for a new ichnotaxonomic name. The settlement and development of the symbiont on living colonies of bryozoan hosts formed sets of tubes with terminal openings that do not occur in non-symbiotic bryozoans, thus modifying the normal growth of its living substrate. Consequently, C. badalloi n. isp. is considered herein as belonging to the ethological category of impedichnia in the absence of a universally accepted criterion on the status of bioclaustration structures. The diagnosis of the ichnogenus Caupokeras is emended.