PlantaeDB Logo
Login Sign-up

Genus Senecio in Tribe Senecioneae

In botanical taxonomy, a genus (plural genera) is a rank used to group closely related species within a family. In the hierarchy, genus sits below family and above species.

Genera are defined by shared morphological, anatomical, and genetic characteristics (for example, features of flowers, fruits, seeds, or leaves) that indicate a close evolutionary relationship among the species they contain.

Each genus can include one or more species. Examples include Rosa (roses) and Solanum (nightshades, including tomato and eggplant).

Do you wish to read more about plant taxonomy? Click here!

Genus Description

Suggest a correction!

Senecio (authority L.) is placed in Asteraceae and contains about one thousand species distributed worldwide, with highest richness in temperate mountains and open habitats, including sea level to alpine zones; the type species is Senecio vulgaris. The genus is diagnosed by herbaceous to shrubby habit, often with lobed or dissected leaves, variable indumentum and small to absent stipules, capitula that are solitary or arranged in corymbs or panicles, and a radiate or disciform involucre of one row of outer phyllaries often accompanied by a few bracteoles. Florets vary from few to many, involucres are usually cylindrical to campanulate, and fruits are achenes with a pappus of soft hairs facilitating wind dispersal. Ovary position is inferior, and the ovule is anatropous with basal placentation, typical of the family.

Diversity and range show major centers in South Africa, the Andes, and the Mediterranean, with numerous local endemics in mountains and island systems. Habitats include alpine meadows, dunes, cliffs, forest edges, and ruderal sites; the genus is both widespread and taxonomically difficult, with many species complexes and polyploid series.

Intrinsic biology is dominated by generalist insect pollination with capitula attractive to bees, flies, and lepidopterans; wind dispersal through pappus is well established. Chromosome number is frequently x=10, with numerous aneuploid and polyploid cytotypes documented in regional treatments. Molecular data support a well-supported clade within Senecioneae, but relationships within the genus remain only partially resolved due to rapid radiations and recurrent hybridization.

Taxonomy and phylogeny reflect long-standing complexity. Recent global syntheses maintain a broadly circumscribed Senecio while recognizing historically segregated lineages such as Jacobaea, Packera, Pericallis, Cacalia, and several others; alternative treatments still segregate these groups on different taxonomic ranks (POWO, 2024; WFO, 2024; Pelser et al., 2023). Phylogenomic analyses confirm the paraphyly of a traditional, broad Senecio and highlight the need for further sampling in understudied regions (Pelser et al., 2007; Huang et al., 2022). Multiple subgeneric or sectional frameworks have been proposed for regional species groups, but global taxonomic stability remains a priority.

Human relevance includes horticultural ornamentals such as Senecio cruentus and the dustbowl weed Senecio vulgaris, with variable invasiveness depending on region. Several species are important horticultural subjects, while some become weeds in agriculture and disturbed sites.

Conservation and outlook vary across species; many are common and secure, but numerous narrow endemics are threatened by habitat loss, fragmentation, and climate change. Clarifying species limits and revising regional groups are critical to guide effective conservation and management (POWO, 2024; Huang et al., 2022).

Pick a Species to see its components: