Senecio cambrensis | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Asterales |
Family: | Asteraceae |
Genus: | Senecio |
Species: | S. cambrensis |
Binomial name | |
Senecio cambrensis Rosser | |
Senecio cambrensis, the Welsh groundsel or Welsh ragwort, is a flowering plant of the family Asteraceae. It is endemic to Great Britain and currently known only from North Wales. It is a recently evolved plant that arose as a result of hybridization between two related species.
It was first noticed in 1948 by Horace E. Green at Ffrith in Flintshire, north-east Wales.
The species was described in 1955 by Effie M. Rosser of Manchester Museum using material from the site. It later turned up at a number of sites across the north-east of Wales including Chirk, Brymbo, Queensferry and Colwyn Bay and a herbarium specimen was discovered that had been collected at Brynteg in 1925. [2]
Welsh groundsel is an allopolyploid, a plant that contains sets of chromosomes originating from two different species. Its ancestor was Senecio × baxteri, an infertile hybrid that can arise spontaneously when the closely related groundsel ( Senecio vulgaris ) and Oxford ragwort ( Senecio squalidus ) grow alongside each other. Sometime in the early 20th century, an accidental doubling of the number of chromosomes in an S. × baxteri plant led to the formation of a new fertile species, Welsh groundsel.
Groundsel has a chromosome number 2n = 40; Oxford ragwort 2n = 20; and Welsh groundsel 2n = 60. [3]
It is intermediate in appearance between the parents. It is an erect annual plant that reaches a height of 30 (sometimes 50) cm. The stem and leaves have few or no hairs. The leaves are deeply lobed. The lower leaves have stalks, whereas the upper leaves are attached directly to the stem. The flower heads are cylindrical and usually have 8 to 15 yellow ray florets ("petals") although some are rayless. The ray florets vary in length but are most commonly 4 to 7 mm long. The pollen grains are 30 to 36 micrometres across and usually have 4 pores. [3]
Outside Wales, it was erroneously reported from Shropshire in 1970 [4] and introduced into a school garden in Wolverhampton in the 1990s, where it did not survive.
However, in 1982, Welsh groundsel was discovered at several sites around Edinburgh, Scotland. This population arose independently from the Welsh population; it is believed to date from at least 1974 but now appears to have disappeared with no records since 1993. [5]
Typical habitats of the species include waste ground, roadsides and cracks in walls and pavements. The population fluctuates considerably from year to year, but overall appears to be declining. [6] Threats include spraying to kill weeds, road widening, and infection by the rust Puccinia lagenophorae Cooke, 1884, which can decimate large stands. [7]
Asteraceae is a large family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger family is unclear as the quantity of extant species in each family is unknown. The Asteraceae were first described in the year 1740 and given the original name Compositae. The family is commonly known as the aster, daisy, composite, or sunflower family.
Senecio is a genus of flowering plants in the daisy family (Asteraceae) that includes ragworts and groundsels.
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 herb, native to the Palaearctic and widely naturalised as a ruderal species in suitable disturbed habitats worldwide.
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, but were moved to a different genus based on chromosome numbers, a variety of morphological characters, and molecular phylogenetic evidence.
Senecio ampullaceus, also known as Texas ragwort, Texas squaw-weed, Texas groundsel, and Texas butterweed, is a species of Senecio in the family Asteraceae, receiving its Latin name ampullaceus from its flask shaped flower-head. It is recommended for landscape use in its native Texas.
Senecio viscosus is a herbaceous annual plant of the genus Senecio. It is known as the sticky ragwort, sticky groundsel or stinking groundsel.
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 natural piles of rocks, war-ruined neighborhoods and dry-stone walls. These habitats resemble its well drained natural rocky homeland. The plants have spread via the wind, rail and the activities of botanists. The travels of this short-lived perennial, biennial, or winter annual make it a good subject for studies of the evolution and ecology of flowering plants.
Senecio eboracensis, the York groundsel or York radiate groundsel, is a flowering plant in the daisy family Asteraceae. It is a hybrid between a native and a non-native introduced species, which naturalised in England but the population failed to sustain itself. It was brought back by captive cultivation. It is a self-pollinating hybrid species of ragwort and one of only six new plant species to be discovered in either the United Kingdom or North America in the last 100 years.
Tephroseris palustris, also known by its common names swamp ragwort, northern swamp groundsel, marsh fleabane, marsh fleawort, clustered marsh ragwort and mastodon flower, a herbaceous species of the family Asteraceae. It can be seen most easily when its bright yellow umbel flowers appear from May to early July standing 3 to 4 feet along marshes, stream banks and slough areas where it likes to grow.
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, making it an invasive species. It is grown as an ornamental plant for its satiny foliage and sweet-scented flowers.
Senecio madagascariensis, also known as Madagascar ragwort, is a species of the genus Senecio and family Asteraceae that is native to Southern Africa. Other common names include Madagascar groundsel and fireweed. It has been included on the noxious weeds list for Hawaii and the reject list for Australia. S.madagascariensis is the diploid cytotype of S.inaequidens.
Senecio triangularis, known as arrowleaf ragwort, arrowleaf groundsel and arrowleaf butterweed, is a species of the genus Senecio and family Asteraceae.
Barkleyanthus is a monotypic genus of flowering plants in the aster family, Asteraceae, containing the single species Barkleyanthus salicifolius, a plant formerly classified in the genus Senecio. It is native to North and Central America, where its distribution extends from the southwestern United States to El Salvador. Its common names include willow ragwort, willow groundsel, Barkley's-ragwort, and jarilla.
Senecio aphanactis, known by the common names chaparral ragwort, rayless ragwort, and California groundsel, is a species of flowering plant in the aster family.
Senecio californicus is a species of flowering plant in the aster family known by the common name California ragwort.
Senecio elegans is a species of flowering plant in the aster family known by the common names redpurple ragwort, purple groundsel, wild cineraria and purple ragwort.
Senecio hydrophiloides is a species of flowering plant in the aster family known by the common names tall groundsel and sweet marsh ragwort. It is native to western North America from British Columbia and Alberta to northern California to Utah, where it grows in wet meadows and similar habitat. It is a biennial or perennial herb producing a single erect stem or a cluster of a few stems which may exceed one meter in maximum height. The plants are green to red in color and usually without hairs, but new growth can be woolly. The leaves are lance-shaped to oval with toothed edges, the blades up to 25 centimeters long and borne on long winged petioles. The leaves are firm and sometimes a bit fleshy. The inflorescence is a loose or dense cluster of up to 30 or more flower heads lined with black-tipped phyllaries. They contain many yellowish disc florets at the center and often have some yellow ray florets, though these are sometimes absent. Senecio Hydrophiloides can cause Dermatitis.
Senecio serra is a species of flowering plant in the aster family known by the common names tall ragwort and sawtooth groundsel. It is native to the western United States, where it can be found in several types of habitat, including sagebrush and woodlands. It is a perennial herb producing a single erect stem or a cluster of stems from a branched, woody caudex. The plant can exceed two meters in height. It is hairless in texture, with young plants sometimes appearing fuzzy, and green to red-tinged in color. The leaves have lance-shaped blades up to 20 centimeters long borne on short petioles, the leaves occurring evenly all along the stems. The inflorescence is a spreading array of many flower heads, each lined with green- or black-tipped phyllaries. The heads contain yellow disc florets and 5 to 8 yellow ray florets each under a centimeter long.
Senecio sylvaticus is a species of flowering plant in the aster family. It is variously known as the woodland ragwort, heath groundsel, or mountain common groundsel. It is native to Eurasia, and it can be found in other places, including western and eastern sections of North America, as an introduced species and an occasional roadside weed. It grows best in cool, wet areas. It is an annual herb producing a single erect stem up to 80 centimeters tall from a taproot. It is coated in short, curly hairs. The toothed, deeply lobed leaves are up to 12 centimeters long and borne on petioles. They are evenly distributed along the stem. The inflorescence is a wide, spreading array of many flower heads, each lined with green- or black-tipped phyllaries. The heads contain yellow disc florets and most have very tiny yellow ray florets as well.
Packera musiniensis is a rare species of flowering plant in the aster family known by the common names Musinea ragwort and Musinea groundsel. It is endemic to Utah in the United States, where it is known only from Sanpete County in the Manti-La Sal National Forest.
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