The Cuban ultramafic areas support the highest plant diversity and endemism of the island and are frequently damaged by human activities. In this work we hold up the importance of "El Tibisial" for conserving the ultramafic flora of Guamuhaya region. The 73.3 % of Guamuhaya ultramafic flora and 49 of the 55 endemic plants reported to this region occurs at "El Tibisial" area. In this area 67 species are useful for humans. This area supports two types of plant communities: the spiny xeromorphic thicket on serpentine soil and the secondary spiny xeromorphic thicket on serpentine soil.
