Solanum nelsonii (often misspelled Solanum nelsoni), commonly known as Nelson's Horsenettle, is an annual to perennial plant in the Solanaceae family, part of the Solanum or nightshade genus. This poisonous plant is endemic to the Pacific Islands. It grows low to the ground in sandy soil.Nelson's Horsenettle was first described by Michel Félix Dunal. The scientific name Solanum nelsonii has also – invalidly – been given to two other species of nightshade: S. nelsonii of Zipp. based on Span.