![]() ![]() kamtschaticum (Telephium clade), that has been segregated into Phedimus (tribe Umbiliceae). Įarlier authors placed a number of Sedum species outside of these clades, such as S. Chromosome number is considered an important taxonomic feature. Sedum demonstrates a wide variation in chromosome numbers, and polyploidy is common. There are now thought to be approximately 55 European species. The relationships between the tribes of Sempervivoideae is shown in the cladogram. Therefore the current circumscription, which is somewhat artificial and catch-all must be considered unstable. However the number of species found outside of the first two clades (Tribe Sedeae) are only a small fraction of the whole genus. In addition at least nine other distinct genera appear to be nested within Sedum. Sedum species are found in four of six major crown clades wthin subfamily Sempervivoideae of Crassulaceae and are allocated to tribes, as follows: Clades and tribes within Sempervivoideae Clade Although the genus has been greatly reduced, from about 600 to 420–470 species, by forming up to 32 segregate genera, it still constitutes a third of the family and is polyphyletic. Of the three modern subfamilies of the Crassulaceae, based on molecular phylogenetics Sedum is placed in the subfamily Sempervivoideae. Historically it was placed in the subfamily Sedoideae, of which it was the type genus. Of the genera encompassed by the Crassulaceae family, Sedum is the most species rich, the most morphologically diverse and most complex taxonomically. Sedum was first formally described by Carl Linnaeus in 1753, with 15 species. The extent of morphological diversity and homoplasy make it impossible to characterise Sedum phenotypicaly. ![]() They are characterised by succulent leaves and stems. Sedum is a genus that includes annual, biennial, and perennial herbs. Well-known European species of Sedum are Sedum acre, Sedum album, Sedum dasyphyllum, Sedum reflexum (also known as Sedum rupestre) and Sedum hispanicum. ![]() Various species formerly classified as Sedum are now in the segregate genera Hylotelephium and Rhodiola. There are typically twice as many stamens as petals. The flowers usually have five petals, seldom four or six. The plants vary from annual and creeping herbs to shrubs. They are leaf succulents found primarily in the Northern Hemisphere, but extending into the southern hemisphere in Africa and South America. The genus has been described as containing up to 600 species, subsequently reduced to 400–500. Sedum is a large genus of flowering plants in the family Crassulaceae, members of which are commonly known as stonecrops. Cockerellia ( R.T.Clausen & N.W.Uhl) Á.Löve & D.Löve. ![]()
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