Leaf - flower

In my grand-aunt's garden, there is a flowering plant known as "haalu gauri" which has one of the most unique flowers I've ever seen. The petals are not independant of the leaves, and are not adjoined, but grown in on the leaves near the petiole (the stalk of the leaf) itself. The plant has small Ovid pink leaflets, which gives the appearance of being a flower, but the leaflet grows and the rest of the lamina becomes green, although an ovoid area closest to the petiole remains pink (slightly larger than the size of the original leaflet).
Flowers evolved for the purpose of protecting the inner whorls (androecium and gynacium) and to attract insects for the purpose of pollination. The Haalu Gauri has another evolutionary strategy to combat this. What I wonder is:
1) What are the advantages of this flower over normal flowers
2) If there are other plants with such flowers, or if the HAalu Gauri is really unique.

Unfortunately, a net search in both google and a kannada translation engine ( KannadaKAsturi.com) did not yield the English name of the flower.