The genus Wurdackanthus (Gentianaceae-Helieae) comprises two species restricted to northern South America. Wurdackanthus argyreus is a narrowly distributed species on tepuis of southern Venezuela and northern Brazil, and W. frigidus only occurs in the Lesser Antilles. Recent phylogenetic investigations have shown that Wurdackanthus is paraphyletic with respect to Symbolanthus, and that no clear morphological distinction exists between these two genera. These two genera share several unique morphological, anatomical, and molecular synapomorphies, such as (1) pollen released as tetrads and with a coarsely reticulated exine, especially in the equatorial zone (Symbolanthus-type pollen); (2) elongated dome-like seed testa cells; and (3) molecular characters from the trnL intron, matK, internal transgenic spacer (ITS), and 5S non-transcribed spacer (5S-NTS) DNA regions. Based on the concept of monophyly and the presence of structural support, we here include Wurdackanthus in Symbolanthus and provide new synonymy. The new combinations Symbolanthus argyreus (Maguire) Struwe & K. Gould and S. frigidus (Swartz) Struwe & K. Gould are made herein.
|Original language||English (US)|
|Number of pages||6|
|State||Published - Oct 18 2004|
All Science Journal Classification (ASJC) codes
- Ecology, Evolution, Behavior and Systematics
- Plant Science