Beetle-pollinated flowers don't have nectar, whereas flowers pollinated by bees, flies, and birds do have nectar. Darlingtonia flowers have no apparent nectar, so that would fit the beetle idea. Beetles like to eat pollen--and as you can see, Darlingtonia flowers produce lots of pollen, which the flower is shedding here from its pale yellow stamens, shown above. If beetles eat the pollen, wouldn't that be bad for pollination? No, it's a compromise. Beetle-pollinated flowers produce plenty of pollen, and beetles aren't very efficient feeders, so there always seems to be plenty of pollen left over for a beetle to carry around on its surfaces, transferring that pollen to another flower.