the only two active snap traps—the venus flytrap ("dionaea muscipula") and the waterwheel plant ("aldrovanda vesiculosa")—had a common ancestor with the snap trap adaptation, which had evolved from an ancestral lineage that utilized flypaper traps. their trapping mechanism has also been described as a "mouse trap", "bear trap" or "man trap", based on their shape and rapid movement. however, the term "snap trap" is preferred as other designations are misleading, particularly with respect to the intended prey. "aldrovanda" is aquatic and specialised in catching small invertebrates; "dionaea" is terrestrial and catches a variety of arthropods, including spiders.