Vernonia subgenus Austrovernonia, a new subgenus from South America (Compositae, Vernonieae, Vernoniinae)

Abstract

Vernoniaincana Less. and V.echioides Less. are two semi-aquatic species from southern South American that are referred to as “the semi-aquatic Vernonia of South America” and they have been, until now, retained as members of Vernonia mostly because each had some unusual characters that made them hard to place. Based on an ongoing molecular study, we can now say that V.incana is the sister taxon to all true Vernonia and can therefore be responsibly left in Vernonia but, because of its morphological and geographic differences, it is now assigned to its own subgenus: Vernonia subg. Austrovernonia. Vernoniaechioides is not closely related to V.incana and is now part of a separate investigation. This placement of V.incana as sister to the true Vernonia species brings up the possibility of a South American root for the Vernonia clade and perhaps indicates a propensity in the lineage for growing in or near water. The species V.incana is lectotypified.

1076. Vernonia missurica Raf.: Compositae

“…It includes one of the original super genera, Vernonia Schreb., a genus at one time accounting for c. 1200 species and considered to 'make up the "hell" of a thousand look-alikes' (Keeley et al, 2021: 507), alongside Eupatorium L. (c. 1200 spp., see Hind, 2007) in the Eupatorieae. The Vernonieae, including Vernonia of 17 North American species (of a total of 20see Strother, 2006: 206; although some statements put the total at c. 25see Keeley et al, 2021: 507;Robinson & Funk, 2018 neither providing evidence of the larger number of species), amongst close to 130 genera (e.g. see Keeley et al, 2021;Keeley & Robinson, 2009;Loeuille et al, 2014Loeuille et al, , 2015Robinson, 1980Robinson, , 1999aRobinson, , 1999bRobinson, , 2006Robinson et al, 1980Robinson et al, , 2008Robinson et al, , 2016Robinson & Skvarla, 2006, 2009a, 2009b, 2009c, 2011, and where continued additions to the Old World genera are still being made.…”

“…Vernonia sensu stricto is now apparently restricted to those species in North America (Strother, 2006) and, somewhat strangely, another three in Central America (Vernonia greggii A. Gray -Mexico;Robinson & Funk, 2018), and South America (Vernonia echioides Less. and V. incana Less -Argentina, southern Brazil, Paraguay and Uruguaysee Cabrera & Dematteis, 2009;Cabrera & Klein, 1980;Crist obal & Dematteis, 2003).…”

“…The Vernonieae, including Vernonia of 17 North American species (of a total of 20 – see Strother, 2006: 206; although some statements put the total at c. 25 – see Keeley et al, 2021: 507; Robinson & Funk, 2018 – neither providing evidence of the larger number of species), amongst close to 130 genera (e.g. see Keeley et al, 2021; Keeley & Robinson, 2009; Loeuille et al, 2014, 2015; Robinson, 1980, 1999a, 1999b, 2006; Robinson et al, 1980, 2008, 2010, 2016; Robinson & Skvarla, 2006, 2007, 2009a, 2009b, 2009c, 2010, 2011, 2013), and where continued additions to the Old World genera are still being made.…”