| Asteraceae | |
Tithonia angustifolia
| Hook. & Arn. | Bot. Beechey Voy. 435 | 1841 |
| Asteraceae | |
Tithonia argophylla
| D.C. Eaton | Botany (Fortieth Parallel) 423 | 1871 |
| Asteraceae | |
Tithonia aristata
| Oerst. | Vidensk. Meddel. Dansk Naturhist. Foren. Kjøbenhavn 1852(5–7): 114 | 1853 |
| Asteraceae | |
Tithonia auriculata
| (Brandegee) S.F. Blake | Contr. Gray Herb. 54: 9 | 1918 |
| Asteraceae | |
Tithonia brachypappa
| B.L. Rob. | Proc. Amer. Acad. Arts 27: 174 | 1892 |
| Asteraceae | |
Tithonia calva
| Sch. Bip. | Bot. Voy. Herald 305 | 1856 |
| Asteraceae | |
Tithonia crocosmiflora
| G. Nicholson | | |
| Asteraceae | |
Tithonia decurrens
| A. Gray | Mem. Amer. Acad. Arts, n.s. 4: 85 | 1849 |
| Asteraceae | ! |
Tithonia diversifolia
| (Hemsl.) A. Gray | Proc. Amer. Acad. Arts 19(1): 5 | 1884 [1883] |
| Asteraceae | |
Tithonia excelsa
| (Willd.) DC. | Prodr. 5: 585 | 1836 |
| Asteraceae | |
Tithonia fruticosa
| S. Canby & Rose | Contr. U.S. Natl. Herb. 1(4): 104, pl. 5 | 1891 |
| Asteraceae | * |
Tithonia glaberrima
| Kuntze | Revis. Gen. Pl. 1: 371 | 1891 |
| Asteraceae | ** |
Tithonia helianthoides
| Weinm. ex Steud. | Nomencl. Bot. (ed. 2) 2: 689 | 1841 |
| Asteraceae | ! |
Tithonia helianthoides
| Bernh. | Allg. Teutsch. Gart.-Mag. 2: 156–157, t. 15 | 1826 |
| Asteraceae | |
Tithonia heterophylla
| Griseb. | Bonplandia (Hannover) 6(1): 9 | 1858 |
| Asteraceae | |
Tithonia hondurensis
| La Duke | Rhodora 84(837): 139 | 1982 |
| Asteraceae | |
Tithonia koelzii
| McVaugh | Contr. Univ. Michigan Herb. 9(4): 443, f. 41 | 1972 |
| Asteraceae | |
Tithonia longiradiata
| (Bertol.) S.F. Blake | Bull. Torrey Bot. Club 53(4): 217 | 1926 |
| Asteraceae | |
Tithonia macrophylla
| S. Watson | Proc. Amer. Acad. Arts 26: 140 | 1891 |
| Asteraceae | |
Tithonia ovata
| Hook. | Bot. Mag. t. 3901 | 1841 |
| Asteraceae | |
Tithonia pachycephala
| DC. | Prodr. 5: 585 | 1836 |
| Asteraceae | |
Tithonia palmeri
| Rose | Contr. U.S. Natl. Herb. 1(4): 104 | 1891 |
| Asteraceae | |
Tithonia paneroi
| (B.L. Turner) E.E. Schill. & Panero | Bot. J. Linn. Soc. 167(3): 325 | 2011 |
| Asteraceae | |
Tithonia pedunculata
| Cronquist | Mem. New York Bot. Gard. 12(3): 286–288, f. 1 | 1965 |
| Asteraceae | |
Tithonia pittieri
| (Greenm.) S.F. Blake | Contr. Gray Herb. 54: 9 | 1918 |
| Asteraceae | ** |
Tithonia platylepis
| Sch. Bip. ex Benth. & Hook. | Gen. Pl. 2: 368 | 1873 |
| Asteraceae | |
Tithonia pusilla
| A. Gray | Proc. Amer. Acad. Arts 5: 124 | 1861 |
| Asteraceae | * |
Tithonia recurrens
| A. Gray ex Hemsl. | Biol. Cent.-Amer., Bot. 2(8): 176 | 1881 |
| Asteraceae | |
Tithonia rotundifolia
| (Mill.) S.F. Blake | Contr. Gray Herb. 52: 41 | 1917 |
| Asteraceae | |
Tithonia scaberrima
| Benth. | Vidensk. Meddel. Dansk Naturhist. Foren. Kjøbenhavn 1852(5–7): 91 | 1853 |
| Asteraceae | ** |
Tithonia speciosa
| (Hook.) Klatt | Bull. Soc. Roy. Bot. Belgique 31(1): 203–204 | 1892 [1893] |
| Asteraceae | ! |
Tithonia speciosa
| (Hook.) Hook. ex Griseb. | Cat. Pl. Cub. 155 | 1856 |
| Asteraceae | ** |
Tithonia splendens
| Planch. | Fl. Serres Jard. Eur. 8: 19 | 1852-1853 [1852] |
| Asteraceae | |
Tithonia tagetiflora
| Desf. | Ann. Mus. Natl. Hist. Nat. 1: 49, t. 4. | 1802 |
| Asteraceae | * |
Tithonia tagetiflora
| Lam. | Tabl. Encycl. 3: 284, t. 708 | 1823 |
| Asteraceae | |
Tithonia thurberi
| A. Gray | Proc. Amer. Acad. Arts 8: 655–656 | 1873 |
| Asteraceae | ** |
Tithonia triloba
| Sch. Bip. ex Klatt | Bull. Soc. Roy. Bot. Belgique 31(1): 203 | 1892 [1893] |
| Asteraceae | |
Tithonia tubaeformis
| (Jacq.) Cass. | Dict. Sci. Nat. (ed. 2) 35: 278 | 1825 |
| Asteraceae | |
Tithonia uniflora
| J.F. Gmel. | Syst. Nat., ed. 13[bis] 2(2): 1259 | 1791 [1792] |
| Asteraceae | |
Tithonia vilmoriniana
| Pamp. | Bull. Soc. Bot. Ital. 1908: 133–134 | 1908 |