It was once believed that saltmarsh ascomycetes couldn't make use of marshgrass lignocellulose (LC) -- it is very clear from this beautiful transmission-electron micrograph (courtesy David Porter & Wilma Lingle) that saltmarsh ascomycetes definitely do make extensive use of marshgrass LC. Note: I have recently discovered that the hyphae in this TEM are likely to be of both Phaeosphaeria spartinicola and Mycosphaerella sp. 2 of Kohlmeyer & Kohlmeyer (1979). Many ascomycetes have laccase as one of their oxidases that lyse complex polyphenols like lignin. Here is a qualitative laccase test on a plate containing Buergenerula spartinae -- the pink/purple color indicates that laccase is present (syringaldazine); Phaeosphaeria spartinicola, Mycosphaerella sp. 2, and Phaeosphaeria halima also tested positive (image and test by Justine Lyons).

See Newell et al., 1996, Microscopy Research & Technique 33:32-46.