“…Intergrown organisms are common in reef stromatoporoids too, but they can occur also in bedded limestone (Kershaw, 2013). Both tabulate and rugose corals are the most abundant, but numerous tube-shaped fossils, probably worms (e.g., Tourneur et al, 1994;Zhen and West, 1997;Zapalski and Hubert, 2011), also occur (Kershaw, 2013). It is possible that reef faunas may have played a key role in the evolution of many Palaeozoic symbiotic associations.…”