Sinopsis de las especies de Pyracantha (Rosaceae, Maloideae) naturalizadas en Argentina

Background and aims: The genus Pyracantha has about ten species, widespread as ornamental, naturalized and considered invasive in different parts of the world. Historically, the identification of taxa has been difficult. Three species were reported as naturalized in Argentina, however, no genus revision has been carried out in the country until now. In order to make new contributions to the Argentinean Flora, given the complexity of the genus and the lack of an integral work in this regard, the objective of this contribution is to present a synopsis of the Pyracantha species naturalized in Argentina. M&M: Specimens of each species from different national and international herbaria were studied, and were contrasted with the type specimens. The original descriptions and specific bibliography of each taxon was reviewed. Results: A summary of the five naturalized species is presented. Distribution maps in Argentina are presented in addition to descriptions, a key, diagrams of the main leaf morphological characters and a series of images that allow the identification of the species. Lectotypes for four names are designated. Conclusions: Five species are naturalized in Argentina. P. fortuneana and P. koidzumii constitute new records for the flora of the country. Up to this moment, P. fortuneana represents the species with the most austral distribution and, together with P. angustifolia, are the most distributed species in Argentina. P. koidzumii is restricted mainly to the center-east of Argentina. P. atalantioides and P. coccinea are the less represented species.