Ruehssia is a genus of plants in the family Apocynaceae.

[2][3] Its native range is tropical and subtropical South America.

It is found in Argentina (north-eastern and north-western), Belize, Bolivia, Brazil (north, north-eastern, south, south-eastern and west-central), Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, El Salvador, French Guiana, Guatemala, Guyana, Haiti, Honduras, Jamaica, the Leeward Islands, Mexico (north-eastern, south-eastern and south-western), Nicaragua, Panamá, Paraguay, Peru, Suriname, Trinidad and Tobago, Uruguay, Venezuela and the Windward Islands.

[1] The genus name of Ruehssia is in honour of Carl Andreas Rühsz (1805–1880), the German consul in Puerto Cabello, Venezuela.

[1] As of November 2023[update], Plants of the World Online accepted the following species:[1]