''Senecio'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of flowering plants in the daisy family (

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

) that includes ragworts and groundsels. Variously circumscribed taxonomically, the genus ''Senecio'' is one of the largest genera of flowering plants.

Description

Morphology

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 In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

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 The Juan Fernández Islands () are a sparsely inhabited series of islands in the South Pacific Ocean, reliant on tourism and fishing. Situated off the coast of Chile, they are composed of three main volcanic islands: Robinson Crusoe Island, R ...

Chemistry

Pyrrolizidine alkaloids Pyrrolizidine alkaloids (PAs), sometimes referred to as necine bases, are a group of naturally occurring alkaloids based on the structure of pyrrolizidine. Their use dates back centuries and is intertwined with the discovery, understanding, and ...

are found in all ''Senecio'' species. These alkaloids serve as a natural

biocide A biocide is defined in the European legislation as a chemical substance or microorganism intended to destroy, deter, render harmless, or exert a controlling effect on any harmful organism. The US Environmental Protection Agency (EPA) uses a sli ...

s to deter or even kill animals that would eat them. Livestock generally do not find them palatable. ''Senecio'' species are used as food plants by the

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

e of some

Lepidoptera Lepidoptera ( ) or lepidopterans is an order (biology), order of winged insects which includes butterflies and moths. About 180,000 species of the Lepidoptera have been described, representing 10% of the total described species of living organ ...

species that have developed tolerance for these alkaloids.

Taxonomy

The traditional circumscription of ''Senecio'' is artificial, being

polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...

, even in its new circumscription which is based on genetic data. Despite the separation of many

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

into other genera, the genus still contains species and is one of the largest genera of flowering plants. As no morphological

synapomorphies In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to ...

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 and evolved in the mid- to late

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

Phylogeny

As of 2007, many genera and the whole tribe are in need of revision. Many species currently placed in the genus need to be transferred to other or new genera, and others have been retransferred to ''Senecio''. In its new delimitation the genus is still not

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

. Genera that have been included are the following: * ''

Aetheolaena ''Aetheolaena'' is a genus of flowering plants in the aster family, Asteraceae. Species include: * '' Aetheolaena caldasensis'' * '' Aetheolaena campanulata'' * '' Aetheolaena cuencana'' * '' Aetheolaena decipiens'' * '' Aetheolaena heterophyll ...

'' * ''Culcitum'' * ''

Hasteola ''Hasteola'' is a genus of flowering plants in the daisy family, Asteraceae. ; Species * '' Hasteola kamtschatica'' (Maxim.) Pojark. - Russian Far East, northeastern China, Korea * '' Hasteola praetermissa'' Poljakov - Russian Far East * '' Hast ...

'' * ''

Iocenes ''Iocenes'' is a genus of flowering plants in the daisy family. There is only one known species, ''Iocenes virens'', native to extreme southern South America ( Tierra del Fuego Province in Argentina and Magallanes Region in Chile Chile, ...

'' B. Nord. * ''

Lasiocephalus ''Lasiocephalus'' is a genus of South American flowering plants in groundsel tribe within the sunflower family. The genus was shown to be part of ''Senecio ''Senecio'' is a genus of flowering plants in the daisy family (Asteraceae) that in ...

'' Willd. ex Schltdl. * '' Robinsonia''

Synonyms

The following genera contain species that are or have been included within ''Senecio''. * '' Antillanthus'' B. Nord. * '' Barkleyanthus'' H. Rob. & Brettell * '' Brachyglottis'' J. R. Forst. & G. Forst. * '' Canariothamnus'' B. Nord. * '' Curio'' P.V. Heath * '' Dauresia'' B. Nord. & Pelser * '' Dendrophorbium'' C. Jeffrey * ''

Dendrosenecio ''Dendrosenecio'' is a genus of flowering plants in the sunflower family. It is a segregate of ''Senecio'', in which it forms the subgenus ''Dendrosenecio''. Its members, the giant groundsels, are native to the higher-altitude zones of ten mou ...

'' (Hauman ex Hedberg) B. Nord. - Giant groundsels occurring in the

high altitude Altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context (e.g., aviation, geometry, geographical s ...

areas of

East Africa East Africa, also known as Eastern Africa or the East of Africa, is a region at the eastern edge of the Africa, African continent, distinguished by its unique geographical, historical, and cultural landscape. Defined in varying scopes, the regi ...

* '' Dorobaea'' Cass. * '' Dresslerothamnus'' H. Rob. * ''

Elekmania ''Elekmania'' is a genus of the tribe Senecioneae and the family Asteraceae. All species are endemic to the Caribbean island of Hispaniola, in the Dominican Republic and Haiti. Taxonomy The genus was first published by Bertil Nordenstam in Compos ...

'' B. Nord. * '' Herreranthus'' B. Nord. * '' Hubertia'' Bory * '' Jacobaea'' Mill.'' Leonis'' B. Nord. * ''

Ligularia ''Ligularia'' (leopard plant) is a genus of Old World herbaceous perennial plants in the groundsel tribe within the sunflower family. They have yellow or orange composite flower heads with brown or yellow central disc florets, and are native ...

'' * '' Lundinia'' B. Nord. * '' Mesogramma'' DC. * '' Monticalia'' C. Jeffrey * '' Nelsonianthus'' H. Rob. & Brettell * '' Nesampelos'' B. Nord., nom. inval. * '' Oldfeltia'' B. Nord. & Lundin * ''

Packera ''Packera'' is a genus of about 75 species of plants in the daisy family, Asteraceae. Most species are commonly called ragworts or grounsels. Its members were previously included in the genus ''Senecio'' (where they were called ''aureoid senecios ...

'' Á. Löve & D. Löve * '' Pentacalia'' Cass. * '' Pippenalia'' McVaugh * '' Pittocaulon'' H. Rob. & Brettell * '' Pojarkovia'' Askerova * '' Psacaliopsis'' H. Rob. & Brettell * '' Pseudogynoxys'' (Greenm.) Cabrera * '' Pseudojacobaea'' (Hook. f.) R. Mathur * '' Roldana'' La Llave * '' Sinosenecio'' B. Nord. * '' Synotis'' (C. B. Clarke) C. Jeffrey & Y. L. Chen * '' Telanthophora'' H. Rob. & Brettell * '' Tephroseris'' (Rchb.) Rchb. * '' Vendredia'' Baill. * '' Zemisia'' B. Nord.

Etymology

The

scientific name In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

, ''

Senecio ''Senecio'' is a genus of flowering plants in the daisy family (Asteraceae) that includes ragworts and groundsels. Variously circumscribed taxonomically, the genus ''Senecio'' is one of the largest genera of flowering plants. Description Mo ...

'', derives from the latin 'senex' wich means "old man".

Selected species

*'' Senecio ampullaceus'' — Texas ragwort, Texas squaw-weed, Texas groundsel, clasping-leaf groundsel *''

Senecio angulatus ''Senecio angulatus'', also known as creeping groundsel and Cape ivy, is a succulent flowering plant in the family Asteraceae that is native to South Africa. Cape ivy is a scrambling herb that can become an aggressive weed once established, mak ...

'' L.f. — creeping groundsel *'' Senecio antisanae'' *'' Senecio arborescens'' *'' Senecio barbertonicus'' Klatt — succulent bush senecio *'' Senecio bigelovii'' — nodding groundsel *''

Senecio bosniacus ''Senecio'' is a genus of flowering plants in the daisy family (Asteraceae) that includes ragworts and groundsels. Variously circumscribed taxonomically, the genus ''Senecio'' is one of the largest genera of flowering plants. Description Mo ...

'' G. Beck — Bosnian ragwort *'' Senecio brasiliensis'' (Spreng.) Less. — flor-das-almas *'' Senecio candicans'' — angel wings *'' Senecio cambrensis'' — Welsh groundsel, Welsh ragwort *'' Senecio crassissimus'' *'' Senecio elegans'' — purple groundsel *'' Senecio falklandicus'' *'' Senecio flaccidus'' Less. — Douglas senecio, threadleaf groundsel, threadleaf ragwort *'' Senecio gallicus'' Chaix — French groundsel *'' Senecio glaucus'' L. — Jaffa groundsel *'' Senecio howeanus'' *'' Senecio inaequidens'' — South African ragwort *'' Senecio iscoensis'' — Hieron. *'' Senecio keniophytum'' *'' Senecio lamarckianus'' *'' Senecio leucanthemifolius'' Poir. — coastal ragwort *'' Senecio madagascariensis'' — Madagascar ragwort *'' Senecio macroglossus'' — Natal ivy, wax ivy *'' Senecio neowbsteri'' Olympic Mountain groundsel *'' Senecio patagonicus'' *'' Senecio pauciradiatus'' *'' Senecio pokohinuensis'' — Mokohinau groundsel *'' Senecio pulcher'' *'' Senecio sanmarcosensis'' *'' Senecio scandens'' — climbing Senecio *''

Senecio squalidus ''Senecio squalidus'', known as Oxford ragwort, is a flowering plant in the daisy family Asteraceae. It is a yellow-flowered herbaceous plant, native to mountainous, rocky or volcanic areas, that has managed to find other homes on man-made and n ...

'' — Oxford ragwort *'' Senecio trapezuntinus'' *'' Senecio triangularis'' — arrowleaf groundsel *'' Senecio tropaeolifolius'' — false nasturtium *'' Senecio vaginatus'' *'' Senecio vernalis'' — eastern groundsel *'' Senecio viscosus'' — sticky ragwort *''

Senecio vulgaris ''Senecio vulgaris'', often known by the common names groundsel and old-man-in-the-spring, is a flowering plant in the family Asteraceae. It is an annual plant, annual herbaceous plant, herb, native to the Palaearctic and widely naturalised as a ...

'' — common groundsel, old-man-in-the-spring Formerly in ''Senecio'' * '' Brachyglottis greyi'' (as ''S. greyi'') * ''Pericallis'' × ''hybrida'' (as ''S. cruentus'') * '' Rugelia nudicaulis'' — Rugels ragwort

Distribution

The genus ''Senecio'' is distributed almost worldwide. It is one of the few genera occurring in all five regions with a

Mediterranean climate A Mediterranean climate ( ), also called a dry summer climate, described by Köppen and Trewartha as ''Cs'', is a temperate climate type that occurs in the lower mid-latitudes (normally 30 to 44 north and south latitude). Such climates typic ...

. Furthermore, species are found in mountainous regions, including tropical alpine-like areas.

References

External links

* * * * * * * * * * * * * * * * * {{Authority control Asteraceae genera Taxa named by Carl Linnaeus