Spathiphyllum
Spathiphyllum is a genus of about 47 species of monocotyledonous flowering plants in the family Araceae, native to tropical regions of the Americas and southeastern Asia. Certain species of "Spathiphyllum" are commonly known as spath or peace lilies. They are evergreen herbaceous perennial plants with large leaves 12–65 cm long and 3–25 cm broad. The flowers are produced in a spadix, surrounded by a 10–30 cm long, white, yellowish, or greenish spathe. The plant does not need large amounts of light or water to survive. Etymology. Schott's description of the genus refers to ', where ' is a spathe, and  ' is an adjective modifying spathe, meaning relating to a leaf, and ' means continuing or persisting. "" also means a leaf. Selected species. Species include: Cultivated hybrids include: Cultivation and uses. Several species are popular indoor houseplants. It lives best in shade and needs little sunlight to thrive, and is watered approximately once a week. The soil is best left moist but only needs watering if the soil is dry. The NASA Clean Air Study found that "Spathiphyllum" cleans certain gaseous environmental contaminants, including benzene and formaldehyde. However, subsequent tests have shown this cleaning effect is far too small to be practical . The cultivar 'Mauna Loa' has won the Royal Horticultural Society's Award of Garden Merit. Toxicity. Although it is called a "lily", the peace lily is not a true lily from the family Liliaceae. True lilies are highly toxic (poisonous) to cats and dogs, but the peace lily, "spathiphyllum" is only mildly toxic to humans and other animals when ingested. It contains calcium oxalate crystals, which can cause skin irritation, a burning sensation in the mouth, difficulty swallowing, and nausea, but it does "not" contain the toxins found in true lilies, which could cause acute kidney failure in cats and  some other animals.