<i>Polystichum montevidense</i>Demystified: Molecular and Morphological Data Reveal a Cohesive, Widespread South American Species

The genus Polystichum presents striking variation in morphology and habitat preference in the Central Andes, the Serra do Mar, and adjacent regions. Among these taxa, Polystichum montevidense is a name long applied to an array of twice-pinnate species with dark petiole scales, broad leaves, and no vegetative propagules. Using a classical morphological approach combined with inferences gleaned from molecular data, we analyzed P. montevidense and its widespread and ecologically prominent array of allies. Results from our combined molecular and morphological analysis suggest the name P. montevidense should be applied to collections from the Central Andes south to Argentina, and east to Uruguay and the southernmost portion of Brazil. Most Brazilian plants determined as P. montevidense in herbaria are P. platylepis.