New data on the intergrowth of Rugosa-Bryozoa in the Lower Devonian of North Gondwana

Abstract

Numerous and generally well-preserved examples of the intergrowth Rugosa-Bryozoa from the Upper Pragian and Lower Emsian of the Armorican Massif (Châteaulin and Laval synclinoria), France, and from the Upper Emsian of the Ougarta Mountains, Erg Djemel, Algeria, are described. In the Armorican Massif, the corallites of a rugosan Tryplasmatidae? are intergrown with Ceramoporidae bryozoan close to Crepipora, exceptionally with an unidentified Fistuliporidae (likely a new genus), whereas in Ougarta the coral is not identifiable and is associated with a Fistuliporidae assigned to Fistulipora. Although mainly left in open nomenclature, the material is fully described (structure and microstructure) and illustrated (calcitic skeleton and natural moulds) for the first time. In addition, the presence of Ceramoporidae in the Lower Devonian is clearly established. The evaluation of the association is briefly discussed and a mutualistic relationship supported.