The wildflower Beardtongue or Penstemon gets its name from the hairy area that runs along the floor of its "mouth" looking like a bearded tongue. It is one of those flowers designed just for bumblebees. The size fits them like a glove; the length of its throat, where nectar is stored, is just right for the length of a bumblebee's tongue and the sexual parts of the flower are arranged so they rub the pollen against the back of the visiting bees so they carry it to the next flower.
But when it comes to other insect visitors they are not so welcoming. The outside of the flower is coated by glandular hairs, with shiny droplets of a gooey fluid at their tips. They feel sticky to the touch and, to a small insect, they are a death trap from which they can't disentangle themselves. I assume that they do it for protection although I can't imagine what protection they need from midges and the like.
Here you have one performing both functions at the same time, a welcoming host and a killer all at once.