Stigmidium neofusceliae (Dothideales s.l.), a new lichenicolous fungus from Spain

Stigmidium neofusceliae Calatayud & Triebel (Dothideales s.l.) is described as new to science. It is found in eastern Spain occurring on Neofuscelia. This lichenicolous fungus is compared with the only other Stigmidium specie s currently known as occurring on parmelioid lichens, S. xanthoparmeliarum (new to Spain), and with 'Stigmidium' psorae, which is similar because of i ts cell wall chemistry. S. psorae is regarded as a member of the family Dac ampiaceae but its generic placement still remains uncertain. General consid erations concerning the taxonomic relevance of isolichenan as cell wall com ponent causing the It violet reaction of hymenial gel and walls of vegetati ve hyphae are given.