Carduus horridulus
| Carduus horridulus (Michaux) Persoon, Syn. Pl. 2: 390. 1807. | BASIONYM: Cirsium horridulum Michaux 1803. | |
Carduus pinetorum
| Carduus pinetorum Small, Fl. S.E. U.S. 1308, 1341. 1903. | | TYPE: FLORIDA: Miami-Dade Co.: Cocoanut Grove, 2 & 5 Nov 1901, Small & Nash s.n. (holotype: NY). |
Carduus smallii
| Carduus smallii (Britton) Ahles, J. Elisha Mitchell Sci. Soc. 80: 173. 1964, nom. illegit. | BASIONYM: Cirsium smallii Britton 1920; Carduus pinetorum Small 1903. | |
Carduus spinosissimus
| Carduus spinosissimus Walter, Fl. Carol. 194. 1788. | | TYPE: SOUTH CAROLINA: |
Carduus spinosissimus var. elliottii
| Carduus spinosissimus Walter, var. elliottii (Torrey & A. Gray) Porter, in Porter & Britton, Mem. Torrey Bot. Club 5: 345. 1894. | BASIONYM: Cirsium horridulum Michaux, var. elliottii Torrey & A. Gray 1843. | |
Carduus vittatus
| Carduus vittatus Small, Bull. New York Bot. Gard. 3: 439. 1905. | | TYPE: FLORIDA: Miami-Dade Co.: W of Camp Jackson, May 1904, Small & Wilson 1874 (holotype: NY). |
Cirsium horridulum forma elliottii
| Cirsium horridulum Michaux, forma elliottii (Torrey & A. Gray) Fernald, Rhodora 45: 353. 1943. | BASIONYM: Cirsium horridulum Michaux, var. elliottii Torrey & A. Gray 1843. | |
Cirsium horridulum var. elliottii
| Cirsium horridulum Michaux, var. elliottii Torrey & A. Gray, Fl. N. Amer. 2: 460. 1843. | | |
Cirsium horridulum var. megacanthum
| Cirsium horridulum Michaux, var. megacanthum (Nuttall) D. J. Keil, Sida 21: 214. 2004. | BASIONYM: Cirsium megacanthum Nuttall 1841. | |
Cirsium horridulum var. vittatum
| Cirsium horridulum Michaux, var. vittatum (Small) R. W. Long, Rhodora 72: 45. 1970. | BASIONYM: Carduus vittatus Small 1905. | |
Cirsium megacanthum
| Cirsium megacanthum Nuttall, Trans. Amer. Philos. Soc., ser. 2. 7: 421. 1841. | | TYPE: LOUISIANA: Banks of the Mississippi near New Orleans, s.d., Little s.n. (lectotype: PH). Lectotypified by D. J. Keil, Sida 21: 214. 2004. |
Cirsium pinetorum
| Cirsium pinetorum (Small) Small, Fl. Miami 199, 200. 1913, non Greenman 1905. | BASIONYM: Carduus pinetorum Small 1903. | |
Cirsium smallii
| Cirsium smallii Britton, in Britton & Millspaugh, Bahama Fl. 458. 1920. | BASIONYM: Carduus pinetorum Small 1903. | |
Cirsium smallii forma purpureum
| Cirsium smallii Britton, forma purpureum Murrill, Quart. J. Floida Acad. Sci. 12: 66. 1949. | | TYPE: FLORIDA: Alachua Co.: |
Cirsium vittatum
| Cirsium vittatum (Small) Small, Fl. Miami 199, 200. 1913. | BASIONYM: Carduus vittatus Small 1905. | |
Cnicus horridulus
| Cnicus horridulus (Michaux) Pursh, Fl. Amer. Sept. 507. 1814. | BASIONYM: Cirsium horridulum Michaux 1803. | |
Cnicus spinosissimus
| Cnicus spinosissimus (Walter) Darlington, Fl. Cestr., ed. 2. 438. 1837, non Linnaeus 1753, nec Lapeyrouse 1813. | BASIONYM: Carduus spinosissimus Walter 1788. | |
Cirsium horridulum forma atropurpureum
| Cirsium horridulum Michaux, forma atropurpureum Moldenke, Phytologia 26: 224. 1973. | | TYPE: ALABAMA: Clarke Co.: Atkinson, 7 Apr 1973, Moldenke & Moldenke 26857 (holotype: LL). |