If you like the Alien movies, you'll love the solitary wasp. Take one of my favorites, Eumenes, the potter wasp. She flies up and down tiny branches, diligently seeking small caterpillars. When she finds one, she darts down, grabs it and paralyzes it with a sting. Once it's immobilized, she takes it to a secondary location and carefully massages the prey, squeezing everything out of its gut. After all, if those contents were to spoil, the rot could spread to the victim and kill it prematurely. Then she stings it carefully injecting tiny measured doses of her paralytic venom at selected nerve clusters to assure the paralysis is permanent and total.
Once the prey is cleaned and totally helpless, unable even to squirm, she carries it off to a dried mud cell where she deposits it and a single egg, finally sealing it off with a mud plug. The tiny caterpillar waits in the darkness for the wasp larva to hatch and carefully eat all parts not necessary to sustain the victim's life, once again preserving the food's freshness as long as possible.
They are all called "parasitoids" in contrast to regular parasites, which, like mosquitoes and fleas, leave their hosts alive at the end of the interaction. Once the female has spotted her victim, the end is horrifyingly inevitable. The fact that many of them are extremely specific as to what species they hunt can make them valuable biological control agents. It is good to remember, though, that it is not in a picky eater's interest to eliminate all of its food supply so the wasps will seldom completely eradicate a pest but can be relied on to keep populations in check.
Feed Me, Seymour
It's springtime and my Voodoo lily (Dracunculus vulgaris) is blooming. A member of the arum family, it smells just like rotting meat for the one or two days the flower blooms. These guys don't rely on bees to pollinate them, but on flies and beetles, specifically the kind of flies and beetles that are attracted to dead and decaying animals. While not considered a carnivorous plant, they do attract and often kill a great number of green and blue bottle flies, a carrion beetle or two, and a couple of species I have yet to identify as they all vie for the chance to feast on the rotten meat that isn't there. I have even had buzzards swoop through the garden when the lilies were in bloom.
Unlike true carnivorous plants, this one depends on the insects for pollination services, not nutrition. To the best of my knowledge, it does not gain anything from the dead insects that accumulate in the base of the flower. Although someone with a bunch of radioactive flies and a PET scanner might be able to prove otherwise.
Mostly evolving in nutrient depleted swamps, true carnivorous plants supplement their diets with nitrogen supplied by digesting insects. Species grow on every continent except Antarctica.
Trapping mechanisms range from the simple pitfall traps of Sarracenia, Heliamphora, Cephalotus and Nepenthes, the more complex trap of our local native Darlingtonia californica, to the flypaper sticky traps of Byblis, Drosophyllum, Drosera and Pinguicula, to the intricate active traps of Dionea, Aldrovanda and Utricularia, and the exotic corkscrew spiral trap of Genlisea. There are even some species of fungi that trap nematodes with an inflating noose structure.
I have survived raising many of these interesting plants. A fine reference book on their cultivation is The Savage Garden by Peter D'Amato, the revised edition of which I have not yet had the opportunity to read.
Oh, a hint: Those nifty Venus' fly traps you buy at the nursery will thrive living outdoors so long as they're kept wet, don't freeze solid and get some protection from direct sun, as they would in their native Carolina bogs. Winter dormancy is essential for them to recover in the spring and thrive.