Ascomycota > Lecanoromycetes > Lecanorales > Haematommataceae.
Haematomma is the only genus in the family and it has about 35 species.
Eleven of the species occur on bark and rock in Australia.
They are crustose lichens with a white, grey or greenish-grey thallus.
The surface may be smooth, warty, granular or cracked.
When a prothallus is present it is white and it radiates out from a central point.
There may or may not be soredia.
The apotheca are round or irregular.
They are lecorine with the usually well developed margin the same colour as the thallus.
They may be immersed in the thallus especially when young.
The margin may be covered by the disc in older apotheca.
The disc is red, reddish-brown or orange.