Calliandra ricoana (Leguminosae, Mimosoideae, Ingeae): A new and critically endangered species from Chiapas, Mexico

Calliandra ricoana, a new species of Leguminosae (Mimosoideae, Ingeae), from the state of Chiapas, Mexico, is described and illustrated. Critical examination of C. ricoana in comparison with members of Calliandra section Androcallis, series Macrophyllae shows that it is morphologically similar and presumably closely related to C. macqueenii and C. trinervia var. arborea, but it can be distinguished from these and the other members of the series by a combination of characters, namely the arborescent habit, relatively larger leaflets, short peduncles, homomorphic flowers, longer corollas and longer, exserted staminal tubes.