Nicotiana knightiana is recorded for the first time for the flora of Chile. A new species of Nicotiana, endemic to the coast of the Coquimbo region is described and illustrated. Molecular analysis placed the new species within the N. sect. Paniculatae, as sister to N. cordifolia, an endemic to Juan Fernandez islands. The new species can be considered critically endangered (CR) according to the IUCN categories due to its restricted and fragmented distribution, small population number, and the threat that urbanization and mining activities represent for the conservation of the biodiversity of the area.

Nicotiana knightiana is recorded for the first time for the flora of Chile. A new species of Nicotiana, endemic to the coast of the Coquimbo region is described and illustrated. Molecular analysis placed the new species within the section Paniculatae, as sister to Nicotiana cordifolia, endemic to Juan Fernandez islands. The new species can be considered critically endangered (CR) according to the IUCN categories for its restricted and fragmented distribution, small population number, and the threat that urbanization and mining activities represent for the conservation of the biodiversity of the area.

Abstract— A new species of Loasa, endemic to the northern Andes of Chile, is described and informally evaluated, under the IUCN criteria for conservation, as Critically Endangered. Molecular analyses based on plastid markers place the new species within the Loasa ser. Macrospermae, with high support, and specifically as sister to Loasa acerifolia. A key to and comparative plates including all the 13 known species of Loasa ser. Macrospermae are provided.