Senecio

Senecio /sɪˈniːʃi.oʊ/[2] is a genus of flowering plants in the daisy family (Asteraceae) that includes ragworts and groundsels. The scientific Latin genus name, Senecio, means “old man”.

Variously circumscribed taxonomically, the genus Senecio is one of the largest genera of flowering plants.

The traditional circumscription of Senecio is artificial, being polyphyletic, even in its new circumscription which is based on genetic data.[3][4] Despite the separation of many species into other genera, the genus still contains c. 1,250 species and is one of the largest genera of flowering plants.[5]

As no morphological synapomorphies are known to determine which species belong to the genus or not, no exact species number is known. The genus has an almost worldwide distribution[3] and evolved in the mid- to late Miocene.[6]

The flower heads are normally rayed with the heads borne in branched clusters, and usually completely yellow, but green, purple, white and blue flowers are known as well.

In its current circumscription, the genus contains species that are annual or perennial herbs, shrubs, small trees, aquatics or climbers. The only species which are trees are the species formerly belonging to Robinsonia occurring on the Juan Fernández Islands.[7]