Taxonomic revision of the South American genus Mulinum (Azorelloideae, Apiaceae)

The genus Mulinum is endemic to southern South America and is ecologically important because of its dominance in the vegetation of the high Andes and the Patagonian steppe. We present a treatment in which 10 species and 3 new varieties are accepted. A diagnostic key to the species is included, and lists of synonyms, morphological descriptions, observations on the morphological affinities between species, review of the relevant literature, illustrations, and distribution maps are provided. We also analyze and resolve nomenclatural problems, and we provide a list of dubious names and excluded names. Six new synonyms are recognized, including the names M. axilliflorum and M. echinus. Mulinum famatinense is considered here a variety of M. triacanthum . The other two varieties recognized are M. spinosum var. hirsutum and M. spinosum var. zechii . The area of distribution for M. crassifolium, M. leptacanthum, M. spinosum, M. triacanthum, and M. ulicinum has been extended. In addition, 27 lectotypes and one neotype are designated.