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 divers and other casual observers. Following is a brief description of the cladistics and taxonomic classification of "Serpula": While the higher taxonomy is fairly well understood, the lower taxonomy within the genus "Serpula" is somewhat confusing, and not yet thoroughly worked out. Earlier sources have described as many as 77 different species and subspecies. However, there are currently only 29 recognized species in the genus "Serpula". The number and names of these species may soon change as a result of an ongoing revision of the genus by taxonomists. Worldwide,very common. Pacific, Atlantic, and Indian oceans, Mediterranean Sea, North Sea, Red