Size matters: How good are bladderwort traps as suction feeding predators?

Among the carnivorous plants with active traps, bladderworts (genus Utricularia) hold the record for being both extremely fast and extremely small: their underwater suction traps capture zooplankton prey in less than five milliseconds and the traps are often less than two millimeter in diameter. Common sense predicts that the larger the trap, the more energy it costs to set the trap, but also the larger the chance of catching prey. Lab experiments on predator-prey interactions support both predictions, but also pose new puzzles – they cannot explain the high trap speed.