Hypoxylon.
Ascomycota > Ascomycetes > Xylariales.
Most grow on dead wood and some are host specific.
The fruit-bodies can be flat, cushion-like, disc-like, spherical or hemi-spherical, with a broad or
narrow attachment to the substrate.
They may be solitary or confluent.
The surface may be black (like Annulohypoxylon) but many are coloured – sepia, olive, brown, chestnut,
dark brick or greyish sepia.
There may be a granular layer of tissue under the surface and between the peritheca.
This layer can be dull reddish brown, dull orange, rust, dark brown, black or light ochre.
The tissue below the peritheca, about 1 mm thick, may be black, dark brown, white or greyish.
The surface many be smooth or the peritheca may form slight or obvious bumps.
The peritheca are variously shaped – round, oval or tubular.
The apical openings or ostioles may be at any level compared to the stromatal surface.
There may or may not be a disc around the ostioles.
J.F.
