Nomenclatural clarifications and taxonomic circumscription of Schinus areira (Anacardiaceae) in Argentina

Abstract

Schinus areira, an originally South American species, is naturalized in the northwest and west of Argentina, and has a great morphological affinity with S. molle, with which it shares part of its distribution range. Throughout their taxonomic history, both species have been treated as independent species, as a single species with two varieties or synonymized under the same taxon. The objective of this work was to review the taxonomy of S. areira, to redefine the diagnostic characters of the morphology that clearly differentiate it from S. molle in Argentina, and to perform nomenclatural clarifications. As a result, the specimens deposited in the LINN herbarium are discarded as possible types and the name of S. areira is lectotypified by means of an illustration. On the other hand, the following vegetative characters of S. areira were identified with taxonomic value: leaf dimorphism in the same branch, presence of wings in the rachis, and number of pairs and margin of leaflets. Additionally, a dichotomous key is presented to separate S. areira from S. molle.