Serpula (fungus) are formed. The strand mycelium of "Serpula", which can be up to 8 mm thick, are invasive and can spread over non-nutritive surfaces to find new food sources, even spreading through pores in stone, brickwork, and cement. After its initial growth period, the fungus can produce the water it needs and can continue growth into dry timber, eventually degrading it to powder—hence the term "dry rot". "S. lacrymans" is the most serious cause of building timber decay in the UK and northern Europe. The "Dictionary of the Fungi" (10th edition, 2008), suggests that the genus contains two species. , the
Serpula vermicularis urchins "Echinus esculentus" and "Psammechinus miliaris", the brittle star "Ophiothrix fragilis", the starfish "Asterias rubens" and the whelk "Buccinum undatum". Red algae grow on the reef in shallow water. The tunicate "Pyura microcosmus" occurs on these reefs, but is seldom seen in other habitats. A large number of cryptic species of microfauna shelter among the tubes. Predators of the worm include sea urchins, starfish, and the wrasses "Crenilabrus melops" and "Ctenolabrus rupestris". Serpula vermicularis Serpula vermicularis, known by common names including the calcareous tubeworm, fan worm, plume worm or red tube worm, is a species of segmented marine polychaete worm