Revision of heliotropium sects. Heliothamnus, heliotrophytum, hypsogenia, plagiomeris and platygine (heliotropiaceae) in Chile

Abstract

A taxonomic revision of the Chilean species of Heliotropium (Heliotropiaceae) is presented, excluding those of sect. Cochranea that were revised in a previous contribution. These species are Heliotropium amplexicaule (sect. Heliotrophytum), H. corymbosum (sect. Heliothamnus), H. curassavicum (sect. Platygyne), H. geissei (sect. Plagiomeris), H. microstachyum (sect. Hypsogenia), H. paronychioides (sect. Plagiomeris) and H. patagonicum (sect. Platygyne). I analyze in detail the nomenclature, iconography, taxonomy, systematics, distribution and bibliography of each species. Heliotropium corymbosum is newly reported for the flora of Chile and the new combination Heliotropium corymbosum var. grisellum is herewith proposed. This taxon is illustrated for the first time. I discuss the presence of two species of Heliotropiaceae erroneously reported for the Chilean flora: Heliotropium angiospermum (sect. Schobera) and Euploca procumbens. I conclude that the family Heliotropiaceae is represented in Chile only by the genus Heliotropium with 24 species, including 17 species previously treated under sect. Cochranea. I provide a key for the determination of all Chilean species of Heliotropium.