You selected Cirsium semidecurrens Richt. This is a synonym for:

Accepted scientific name:
Cirsium palustre (L.) Coss. ex Scop. (provisionally accepted name)
Synonyms:
Carduus chailleti Godr. (synonym)
Carduus laciniatus Lam. (synonym)
Carduus palustris L. (synonym)
Cirsium chailletii Gaudin (synonym)
Cirsium forsteri Loudon (synonym)
Cirsium kochianum (synonym)
Cirsium laciniatum Nyman (synonym)
Cirsium lacteum Schleich. ex W.Koch (synonym)
Cirsium palatinum Sch.Bip. ex Nyman (synonym)
Cirsium parviflorum Lange ex Nyman (synonym)
Cirsium semidecurrens Richt. (synonym)
Cnicus forsteri Sm. (synonym)
Cnicus lacteus Schleich. (synonym)
Cnicus palustris (L.) Willd. (synonym)
Cynara palustris Stokes (synonym)
Common names: -
Classification:
Plantae
Phylum Magnoliophyta
Class Magnoliopsida
Order Asterales
Family Asteraceae
Genus Cirsium
Distribution: -
Additional data: Data Providers: African Flowering Plants Database, New Zealand Plant Name Database, LCR Editor, Govaerts World Compositae Checklist A-G, IPNI, Tropicos, Euro+Med. GCC LSID: urn:lsid:compositae.org:names:A7F8CC7C-3E97-4C46-9A06-1A6805A8626F
Source database: GCC, 1 (Beta), Nov 2009
Latest taxonomic scrutiny: Flann C., 17-Nov-09
Online resource: -
CoL taxon LSID: urn:lsid:catalogueoflife.org:taxon:1f057c3e-60a7-102d-be47-00304854f810:ac2010