Haematomma is a genus of crustose lichens established by Abramo Bartolommeo Massalongo in 1852. It is the sole genus in the Haematommataceae, a family circumscribed by Josef Hafellner in 1984. Commonly called bloodstain lichens, the species assigned to this genus are widely distributed in tropical and temperate areas.

The genus name Haematomma means "bloody eye", a reference to the color of the lichen's apothecia.

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