Dry rot species of fungi cause brown rot decay, preferentially removing cellulose and hemicellulose from the timber leaving a brittle matrix of modified lignin. The term "dry rot" is somewhat misleading, as both species of fungi "Serpula lacrymans" and "Meruliporia incrassata" require an elevated moisture content to initiate an attack on timber (28–30%). Once established, the fungi can remain active in timber with a moisture content of more than 20%. At relative humidities below 86 percent, growth of "Serpula lacrymans" is inhibited, but it can stay dormant at relative humidities down to 76 percent. These relative humidities correspond to equilibrium moisture contents
Serpula boats in many coastal areas around the world. They are found at depths ranging from intertidal to at least 800 meters. Predators include predatory starfish such as the Ochre Sea Star ("Pisaster ochraceous"). "Serpula" has lived since the Cretaceous period, according to fossils found in the Cretaceous Black Creek Formation of North Carolina. The funnel-shaped, symmetrical peristomium is fused with the prostomium to form the head, at the anterior end of the body. Worms of the genus "Serpula" have two photoreceptors or "eyespots" on the peristomium. The prostomium bears a branchial "crown", a specialized mouth appendage which resembles a fan