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 but comparison with other serpulids suggests it may be between six days and two months, although in other species the period has been shown to vary with season, salinity or food availability, and delayed settling may cause reduced discrimination of substrata during settling (see ten Hove, 1979 for additional references). Worms of the genus "Serpula" are filter feeders, and possess a complete digestive system. Like other polychaetes, "Serpula" excrete with fully developed nephridia. Click here to see more photographs of various specimens of the genus "Serpula". Serpula Serpula (also known as calcareous tubeworm, serpulid tubeworm, fanworm, or plume worm) is