Three new species of Nothoscordum (Amaryllidaceae) from the Campos eco-region of the Grassland Ecosystems of Río de la Plata, Southeast South America

Three new Amaryllidaceae species are described: Nothoscordum elongatum Deble & B. P. Moreira, N. parvum Deble & B. P. Moreira and N. urutauense Deble & H. A. Keller. Nothoscordum elongatum and N. parvum grow in central-eastern Rio Grande do Sul state, while N. urutauense is narrowly endemic to southern Misiones Province, northeast Argentina. The three new taxa are characterized by a strong alliaceous odor, pilose leaves and scapes, and 1 or 2-flowered inflorescence. Nothoscordum elongatum is segregated from N. marchesii by its densely pilose leaves and scapes (vs. glabrous leaves and scapes), flowers with longer pedicels and ovaries with fewer ovules per locule. Nothoscordum parvum is similar to N. modestum and N. urutauense; however, it can be readily separated from both species by the presence of bulbils surrounding the main bulb, the flowers that are narrowly infundibuliform, fused towards the base for 1.8-2.2 mm, and the scapes that are erect at fruit maturity. Nothoscordum urutauense differs from N. inundatum by its broader leaves, flowers with tepals fused at the base for 0.5-1 mm, and free filaments at base. These three species of Nothoscordum are described, illustrated, compared with morphologically similar taxa, and featured with their geographic distribution. In addition, a key to distinguish the 1- or 2-flowered species of Nothoscordum is proposed.