Common

Buttercups are amongst the commonest of all wild flowers and tend to be taken for granted because of that, but they represent a vital, reliable resource for wildlife at the bottom of the food chain. All that pollen supplies food for an amazing array of small insects. 

This young earwig, was nibbling buttercup petals....

............ while this unidentified beetle was feeding on the stamens........

.... and this hoverfly was making a meal of the pollen.

Understandably, naturalists tend to be obsessed with rarities, but it's the common stuff that's really important when it comes to maintaining the stability of  ecosystems.