Nematanthus is a genus of flowering plants of the family Gesneriaceae. All of its species are endemic to Brazil. Compared to other gesneriads, Nematanthus has leaves that are small, succulent, and hard-surfaced. The plant has a trailing, branching, and spreading habit; it is generally an epiphyte in nature and a hanging-basket plant in cultivation. The flower has petals fused into a pouch-like shape, with a small opening. The fancied resemblance of the flower to a goldfish gives the plant its common name, "goldfish plant." Hummingbirds often will feed from the nectar-filled "goldfish" flowers.