Kingcup

Kingcup is a common name used for several species of plants, most notably those in the genus Caltha. The most well-known species is Caltha palustris, also commonly called marsh-marigold. These are perennial herbaceous plants belonging to the buttercup family, Ranunculaceae. They are typically found in wet, marshy areas, along the edges of ponds, streams, and in damp meadows.

The appearance of kingcups is characterized by their glossy, bright yellow flowers, which resemble buttercups. These flowers are usually five-petaled, though sometimes more. The leaves are typically kidney-shaped or heart-shaped, with scalloped edges, and are often dark green. Kingcups often bloom in spring, adding vibrant color to wetland landscapes.

While visually appealing, all parts of the kingcup plant are considered poisonous if ingested. This is due to the presence of protoanemonin, a compound that can cause irritation to the digestive system. Despite their toxicity, kingcups have historically been used in some folk medicine practices, though this is not recommended. The plant's common name, kingcup, is thought to derive from the appearance of its golden flowers, resembling a cup fit for royalty. In some regions, other plants may also be referred to as kingcups, but Caltha palustris is the most widely recognized.