Do both Butea and Calanthe have just two species?
Butea Butea is a genus of flowering plants belonging to the pea family, Fabaceae. It is sometimes considered to have only two species, "B. monosperma" and "B. superba", or is expanded to include four or five species.
Erica Erica is a genus of roughly 860 species of flowering plants in the family Ericaceae. The English common names "heath" and "heather" are shared by some closely related genera of similar appearance. The genus "Calluna" was formerly included in "Erica" – it differs in having even smaller scale-leaves (less than 2–3 mm long), and the flower corolla consisting of separate petals. "Erica" is sometimes referred to as "winter (or spring) heather" to distinguish it from "Calluna" "summer (or autumn) heather".