Pinguicula vulgaris

It grows to a height of 3–16 cm, and is topped with a purple, and occasionally white, flower that is 15 mm or longer, and shaped like a funnel. This butterwort grows in damp environments such as bogs and swamps, in low or subalpine elevations.[1] Being native to environments with cold winters, they produce a winter-resting bud (hibernaculum). There are three forms originating from Europe: P. vulgaris f. bicolor, which has petals that are white and purple; P. vulgaris f. albida, which has all white petals; and P. vulgaris f. alpicola, which has larger flowers.[2] The taxonomic status of these forms is not universally recognised - see e.g. The Plant List.[3]

Common butterwort is an insectivorous plant. Its leaves have glands that excrete a sticky fluid that traps insects to its leaves; its glands also produce digestive enzymes that work to consume the insects externally.[4] This serves as a way for the plant to access a source of nitrogen, as they generally grow in soil that is acidic and low in nutrients, such as bogs.[4][5] Insect capture is an adaptation to nutrient-poor conditions, and the plant is highly dependent on insects for nitrogen.[6]

It has a generally circumboreal distribution, being native to almost every country in Europe as well as Russia, Canada, and the United States.[5][7] It is generally found growing in places such as bogs, fens, alvars, and other areas with limestone bedrock and alkaline waters.[5]

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  Flower from the side, Niitvälja bog, Estonia
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  Whole plant, Norway
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  Pinguicula vulgaris near Mývatn, northern Iceland

• USDA Plants Profile
• Forest Service Ecology