Not all butterflies are flower-visitors. Only the more evolved species and the ones in which the mouth-parts are represented by a long, thin proboscis adapted for feeding on liquid diet pay their visits to flowers. 

Such members include all species of Nymphalids, the majority of males of Lycaenids, Papilios, Pierids and Hesperiids. The flowers are exploited by the butterflies for nectar, the only source of carbohydrate for them. 

Baker and Baker (1973) showed that butterfly nectars tend to have sucrose dominance and are not very viscous. Further, the nitrogen requirement is fulfilled from the amino acids in nectar; therefore the butterfly nectars are normally rich in amino acids.

There is only one known instance of butterflies getting amino acids from pollen. The neotropical butterflies of the genus Heliconius collect pollen on their tongues, add nectar, and then drink the nectar that contains amino acids that have been leached out of the pollen (Gilbert 1972). Nectar may also satisfy the water requirement of butterflies. 

Pic & Post: #SwarnaChakrabarty #SvasaraNaturalist 

(A butterfly from the Hesperiidae Family , A DART (Telicota sp.) nectaring from the Hyptis suaveolens plant)