In article , Alan Gould
writes
Thanks Stewart. The plot re. plant relationship thickens here a bit, but
all of those you mention are in the Compositae family, though in
different genera and species of that group. Some of them are also
mentioned as species or sub-species within the Asteraceae family, and
use the synonym Lactuca for differentiation. Plantfinder gives twenty
varieties of Sow-thistle, with the common Sow-thistle listed as Sonchus
oleraceus.

Cardueae and Lactuceae (or Cichorieae) are subdivisions of Compositae; I
took that as understood. Asteraceae and Compositae are the same.

[The current rules are that family names are derived from generic names,
but some old family names are grandfathered in

Leguminosae = Fabaceae
Guttiferae = Hypericaceae
Graminales = Poaceae
Labiatae = Lamiaceae
Compositae = Asteraceae
Cruciferae = Brassicaceae
Umbelliferae = Apiaceae

and any more I've forgotten.]
--
Stewart Robert Hinsley