Wikipedia
Cardiopteridaceae is a eudicot family of flowering plants. It consists of about 43 species of trees, shrubs, and woody vines, mostly of the tropics, but with a few in temperate regions. It contains six genera, the largest of which is Citronella, with 21 species. The other genera are much smaller.
Citronella mucronata is grown as an ornamental for its attractively shiny leaves and fragrant flowers. A tea is made from the leaves of Citronella gongonha which is similar to yerba maté.
The APG III classification (2009) places them in the order Aquifoliales. This order consists of Cardiopteridaceae, its sister family, Stemonuraceae, and the three monogeneric families Phyllonomaceae, Helwingiaceae, and Aquifoliaceae.