ROBINSON, HAROLD. Smithsonian Institution, Department of Botany, NHB-166, Washington, DC 20560. - Misadventures in the Senecioneae.
Errors in Senecioneae classification are reviewed with mention of
reasons for the errors. Gongrothamnus (Distephanus, Vernonieae),
Liabum (Liabeae), Eremothamnus (Eremothamneae, near Arctoteae) - all
Cichoriodeae, Schistocarpha and Neurolaena (paleaceous Heliantheae)
and Arnica (Helenieae-Heliantheae), all with yellow flowers and
capillary pappus, remained in the Senecioneae until the 1970's and
1980's as a relict of the overly broad Senecionideae of Lessing (1832)
and Candolle (1836-7). At the same time the Blennospermatinae were
usually excluded. Weber (1973) wrongly tranferred western United
States species of Senecio to the asiatic genus Ligularia because of
the smell of the specimens in herbarium cases. The name Cacalia was
broadened and then misattributted by Linnaeus (1753) and Cassini
(1816) for taxonomic convenience. Cacalia was defined by lack of rays
and lack of yellow flowers, which excluded most of the closest
relatives of the concept such as Ligularia but included the remote
group Mulgediifolii. The term Cacalioid continued to be used for the
previous group now known as the Tussilagineae. True Cacalia is
European, with 4-lobed corollas, and is now properly placed in the
subtribe Adenostylinae. Packera has been separated from Senecio
because of differences in chromosome number. The reliance on
chromosome study and TEM sections of pollen to justify the genus is
questioned.
Key words: Arnica, Cacalia, Ligularia, Mistakes, Packera, Senecioneae