New combinations in the South American genera Lepidaploa and Lessingianthus (Vernonieae, Asteraceae)

Abstract

The genera Lepidaploa (Cass.) Cass. and Lessingianthus H. Rob. (Vernonieae, Asteraceae) were established to separate
taxa initially placed in Vernonia Schreb. sect. Lepidaploa (Cass.) DC. subsect. Axilliflorae Benth. & Hook. and Vernonia
sect. Lepidaploa subsect. Macrocephalae Benth. & Hook., respectively. As presently delimited, Lepidaploa is comprised of
about 150 species widely distributed in South America, while Lessingianthus presents 120 species having a concentration in
southeastern Brazil. It is estimated that a large amount of several species still included in Vernonia have not been examined
and consequently their taxonomic position remains uncertain. We analyzed pollen morphology and floral microcharacters
of several Vernonia species, which allowed the transfer of six taxa previously placed in this genus to Lessingianthus and
other two species of the Vernonia to Lepidaploa.