Agradecimentos: We thank Alexandre Salino of the BHCB herbarium; Samarco Mineração S.A., in the names of Gilciana Milagres and Ana Paula Correa, and Amplo Engenharia for financial support; Belkiss Radicchi Alméri for drawings; Cristiano Vidal and Núbia Campos for field expeditions to find new individuals. Thanks to Instituto Estadual de Florestas (IEF) and Instituto Chico Mendes de Conservação da Biodiversidade (ICMBio) for authorizations and Itambé State Park for authorization to collect. We also thank Editage for English language editing Ver menos

Abstract: The Quadrilátero Ferrífero (Iron Quadrangle [IQ]), in Minas Gerais, Brazil, exhibits high geological and geomorphological diversity, reflected by its high heterogeneity of vegetation. Its rock outcrops, particularly ironstone, harbor endemic-rich plant communities and contribute substantially to the biodiversity of the biomes they are embedded within the Atlantic Rainforest and Cerrado region. The aim of this study was determining the distribution, phenology and state of conservation of one new species for science with occurrence in the Quadrilátero Ferrífero. Random walks were carried out in the areas of potential occurrence of the species and individuals were collected to allow description. The plant species was identified and categorized as being new to science and known only from this location: Agalinis marianae (Orobanchaceae). This new species is morphologically similar to A. itambensis but can be recognized by the smaller pedicels and the shape of the corolla. The distinct geographic distribution of these species is an additional factor that supports this separation. Here, we describe and illustrate A. marianae, and provide notes on its distribution, habitat, phenology, and conservation status. We also present a key to the species of Agalinis from Minas Gerais Ver menos