Article: Biology of the Famennian heterocoral Oligophylloides pachythecus

Studies on the taxonomy and morphology of the Famennian heterocoral Oligophylloides have placed great emphasis on the character of the soft tissue, coloniality and distal development of the skeleton with regard to the construction of the wall. Here, the existence of soft tissue covering the entire skeleton of the colony is proposed. Thirty-eight branching specimens have been found in addition to the predominant single fragments of corallites; these should be regarded as colonial with a well-developed branching form. It is here proposed that the external wall grew not only at the distal end, and that its thickening did not result from the overlapping of tabulae, but was built independently of tabulae by the soft tissue covering the whole skeleton of the colony. The following new characteristics of Oligophylloides are described: a change in the position of septa, so-called 'septal shifting', a rearrangement of the septal apparatus; the occurrence of aulos-like structures; a groove ornamentation on the external wall; and the granular microstructure of the axial part of septa. A detailed study of Late Devonian Oligophylloides corals shows that O. tenuicinctus Roz.kowska and O. pachythecus pentagonus Roz.kowska are synonymous with O. pachythecus Roz.kowska.