A new genus and species of colonial rugose coral from late Tournaisian (Waulsortian) mud-mounds in Ireland: Its ecological associations and depositional setting

Abstract

A new genus and species of fasciculate rugose coral, Howthia suttonensis Somerville and Rodríguez, has been recorded from Howth peninsula, County Dublin, Ireland, in Waulsortian mud-mound limestones of upper Tournaisian age. The new colonial genus is characterized by having an axophyllid axial structure, steeply inclined tabellae, and presence of interseptal and lonsdaleoid dissepiments. It evolved probably from a solitary Axophyllum by the development of peripheral offsets. This new taxon may have been an ecological pioneer adapting to a specialised niche near the top of a large Waulsortian mud-mound in shallower water than most Waulsortian settings and, as such, may have provided a novel evolutionary opportunity. Howthia suttonensis is associated with Amplexocarinia and an unusual form of ‘ Fasciculophyllum’, both of which display budding and protocoloniality, as well as the fasciculate tabulate coral Syringopora.