You selected Mesadenia lanceolata (Nutt.) Raf. This is a synonym for:

Accepted scientific name:
Arnoglossum ovatum (Walter) H.Rob. (provisionally accepted name)
Synonyms:
Cacalia elliottii (R.M.Harper) Shinners (synonym)
Cacalia lanceolata Nutt. (synonym)
Cacalia maxima (R.M.Harper ex R.M.Harper) Shinners (synonym)
Cacalia ovata Walter (synonym)
Conophora maxima Nieuwl. (synonym)
Conophora ovata (Walter) Nieuwl. (synonym)
Mesadenia angustifolia Rydb. (synonym)
Mesadenia dentata Raf. (synonym)
Mesadenia elliottii R.M.Harper (synonym)
Mesadenia lanceolata (Nutt.) Raf. (synonym)
Mesadenia maxima R.M.Harper (synonym)
Mesadenia ovata (Walter) Raf. (synonym)
Senecio boscianus Sch.Bip. (synonym)
Senecio walteri Sch.Bip. (synonym)
Common names: -
Classification:
Plantae
Phylum Magnoliophyta
Class Magnoliopsida
Order Asterales
Family Asteraceae
Genus Arnoglossum
Distribution: -
Additional data: Data Providers: Govaerts World Compositae Checklist A-G, IPNI, Tropicos. GCC LSID: urn:lsid:compositae.org:names:F1F5DB74-9031-4326-BCE8-ACB2F05145D3
Source database: GCC, 1 (Beta), Nov 2009
Latest taxonomic scrutiny: Flann C., 10-Aug-09
Online resource: -
CoL taxon LSID: urn:lsid:catalogueoflife.org:taxon:1f12eb6c-60a7-102d-be47-00304854f810:ac2010