Willowherbs as we know them, pink-flowered species including many natives, are of great value as wildlife plants, important for bee and hoverfly pollinators, but also as larval food plants for many moths, including the dramatic elephant hawk-moth. But the ones mostly grown in gardens are newcomers to the genus, the former Zauschneria species. The orange to red long-tubular flowers from the deserts of North America are in their native home pollinated by hummingbirds. Here it is possible that hummingbird hawk-moths could get at the nectar in the intended way, but our bees have adopted the lifestyle of nectar-thieves, biting a hole in the base of the flower tube, getting what they want without doing what the plant wants: pollination.
Also some Epilobium have been renamed as Chamaenerion.