Carphalea kirondron (Madagascan)
Botanical name: Carphalea kirondron
Common name: Madagascan
Family: Rubiaceae
Origin: Madagascar
An example of a Rubiaceae with enlarged, unequal, colored calyx lobes, long-styled flowers.
Link to this plant:
https://toptropicals.com/catalog/uid/carphalea_kirondron.htm