Utricularia species are aquatic plants native to Ireland that live in bogs and Nitrogen-poor areas. Most plants subject to Nitrogen poor conditions experience poor photosynthesizing processes; Nitrogen is key in the synthesis of proteins and nucleotides, and so plants with Nitrogen deficiencies begin bleaching and eventually die from being unable to photosynthesize. There are plenty of plants that have developed the ability to fix nitrogen themselves - but Utricularia spp. opted for the carnivorous path.
Utricularia have fine leaves and small ~3mm long "bladders". On one side, the bladders have an aperture from which stiff bristles extend in a funnel-like shape. The aperture has a hinged valve which can open inward, and when small insects (worms, larvae) or zooplankton swim by and brush the bristles the valve opens creating a change in pressure and sucking the surrounding water and animals into the bladder. There is no escape for the animals, and they decompose and are digested - providing the plant with its much needed Nitrogen.