Morphometric Analyses and New Taxonomic Circumscription of South American Species of Flourensia (Asteraceae, Heliantheae, Enceliinae)

30 January 2018

Ospina, Juan; Aagesen, Lone; Ariza Espinar, Luis; Freire, Susana E.

Flourensia (Asteraceae, Heliantheae, Enceliinae) is an amphitropical genus of resinous subshrubs, shrubs, and small trees with 13 North American, and 20 South American species where disagreement on the species limits of some of its members still exists. To resolve taxonomic limits among the South American taxa, we carried out a combination of clustering (based on Ward´s method with Gower distance coefficient) and ordination (based on Principal Coordinate Analyses). Thirty-four vegetative and reproductive characters were scored using herbarium material, including types. This study recognizes 12 South American species for the genus Flourensia: F. angustifolia, F. cajabambensis, F. fiebrigii, F. heterolepis, F. hirtissima, F. macrophylla, F. niederleinii; F. peruviana, F. polycephala, F. thurifera, F. tortuosa, and F. suffrutescens. Based upon these results, a number of species are placed in synonymy: Flourensia blakeana and F. hirta, are synonymized under the name F. fiebrigii; Flourensia campestris, F. leptopoda, F. oolepis, and F. riparia, are synonymized under the name F. thurifera; Flourensia macroligulata is synonymized under the name F. tortuosa; Flourensia polyclada is synonymized under the name F. suffrutescens. A taxonomic treatment of four redefined species as well as a key and distribution maps to all South American species are provided.