| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| THSTS | Thouinia striata Radlk. var. striata | ceboruquillo | Sapindaceae
|
| THST2 | Thouinia striata Radlk. | ceboruquillo | Sapindaceae
|
| THOUI | Thouinia Poit. | thouinia | Sapindaceae
|
| THFL5 | Thrinax floridana Sarg. | Thrinax radiata | Arecaceae
|
| THKE | Thrinax keyensis Sarg. | Thrinax morrisii | Arecaceae
|
| THMI8 | Thrinax microcarpa Sarg. | Thrinax morrisii | Arecaceae
|
| THMO4 | Thrinax morrisii H. Wendl. | Key thatch palm | Arecaceae
|
| THMU | Thrinax multiflora sensu R.W. Read, non Mart. | Thrinax radiata | Arecaceae
|
| THPA8 | Thrinax parviflora auct. non Sw. | Thrinax radiata | Arecaceae
|
| THPO6 | Thrinax ponceana O.F. Cook | Thrinax morrisii | Arecaceae
|
| THPR2 | Thrinax praeceps O.F. Cook | Thrinax morrisii | Arecaceae
|
| THRA2 | Thrinax radiata Lodd. ex J.A. & J.H. Schultes | Florida thatch palm | Arecaceae
|
| THRIN | Thrinax Sw. | thatch palm | Arecaceae
|
| THAL4 | Thrincoma alta O.F. Cook | Coccothrinax barbadensis | Arecaceae
|
| THDI6 | Thrombium discordans (Nyl.) Zahlbr. | | Thrombiaceae
|
| THEP2 | Thrombium epigaeum (Pers.) Wallr. | | Thrombiaceae
|
| THMO10 | Thrombium mongolicum H. Magn. | | Thrombiaceae
|
| THROM | Thrombium Wallr. | thrombium | Thrombiaceae
|
| THAN2 | Thryallis angustifolia (Benth.) Kuntze | Galphimia angustifolia | Malpighiaceae
|
| THGR5 | Thryallis gracilis (Bartl.) Kuntze | Galphimia gracilis | Malpighiaceae
|
| THIN13 | Thuarea involuta (G. Forst.) Roemer & J.A. Schultes | Kuroiwa grass | Poaceae
|
| THUAR | Thuarea Pers. | Kuroiwa grass | Poaceae
|
| THAB70 | Thuidium abietinum (Hedw.) Schimp. in B.S.G. | Abietinella abietina | Thuidiaceae
|
| THAL8 | Thuidium allenii Aust. | Allen's thuidium moss | Thuidiaceae
|
| THBO3 | Thuidium bolanderi (Best) Par. | Claopodium bolanderi | Leskeaceae
|
| THCR2 | Thuidium crispifolium (Hook.) Lindb. | Claopodium crispifolium | Leskeaceae
|
| THDER | Thuidium delicatulum (Hedw.) Schimp. in B.S.G. var. radicans (Kindb.) Crum et al. | Thuidium philibertii | Thuidiaceae
|
| THDER2 | Thuidium delicatulum (Hedw.) Schimp. in B.S.G. var. repens Kindb. | Thuidium delicatulum | Thuidiaceae
|
| THDE10 | Thuidium delicatulum (Hedw.) Schimp. in B.S.G. | delicate thuidium moss | Thuidiaceae
|
| THIN12 | Thuidium involvens (Hedw.) Mitt. | Cyrto-hypnum involvens | Thuidiaceae
|
| THLA10 | Thuidium lanatum (Brid.) Hag | Helodium blandowii var. blandowii | Helodiaceae
|
| THLE8 | Thuidium leuconeuron (Sull. & Lesq.) Lesq. | Claopodium whippleanum | Leskeaceae
|
| THLI8 | Thuidium lignicola Kindb. | Bryohaplocladium microphyllum | Leskeaceae
|
| THMIL | Thuidium microphyllum (Hedw.) Jaeg. var. lignicola (Kindb.) Best | Bryohaplocladium microphyllum | Leskeaceae
|
| THMIO | Thuidium microphyllum (Hedw.) Jaeg. var. obtusum Grout | Bryohaplocladium microphyllum | Leskeaceae
|
| THMI13 | Thuidium microphyllum (Hedw.) Jaeg. | Bryohaplocladium microphyllum | Leskeaceae
|
| THMI14 | Thuidium minutulum (Hedw.) Schimp. in B.S.G. | Cyrto-hypnum minutulum | Thuidiaceae
|
| THPA10 | Thuidium paludosum (Sull.) Rau & Herv. | Helodium paludosum | Helodiaceae
|
| THPH2 | Thuidium philibertii Limpr. | Philibert's thuidium moss | Thuidiaceae
|
| THPS | Thuidium pseudo-gracile Kindb. | Bryohaplocladium virginianum | Leskeaceae
|
| THPY3 | Thuidium pygmaeum Schimp. in B.S.G. | Cyrto-hypnum pygmaeum | Thuidiaceae
|
| THRE7 | Thuidium recognitum (Hedw.) Lindb. | thuidium moss | Thuidiaceae
|
| THSC2 | Thuidium schistocalyx (C. M�ll.) Mitt. | Cyrto-hypnum schistocalyx | Thuidiaceae
|
| THSCA | Thuidium scitum (P. Beauv.) Aust. var. aestivale Aust. | Rauiella scita | Thuidiaceae
|
| THSC3 | Thuidium scitum (P. Beauv.) Aust. | Rauiella scita | Thuidiaceae
|
| THTA2 | Thuidium tamariscinum (Hedw.) Schimp. in B.S.G. | tamarisk thuidium moss | Thuidiaceae
|
| THVI4 | Thuidium virginianum (Brid.) Schimp. in Besch. | Bryohaplocladium virginianum | Leskeaceae
|
| THUID | Thuidium Schimp. in B.S.G. | thuidium moss | Thuidiaceae
|
| THOC2 | Thuja occidentalis L. | arborvitae | Cupressaceae
|
| THOR | Thuja orientalis L. | Platycladus orientalis | Cupressaceae
|
| THPL | Thuja plicata Donn ex D. Don | western red cedar | Cupressaceae
|
| THUJA | Thuja L. | red cedar | Cupressaceae
|
| THAL3 | Thunbergia alata Bojer ex Sims | blackeyed Susan vine | Acanthaceae
|
| THER | Thunbergia erecta (Benth.) T. Anders. | bush clockvine | Acanthaceae
|
| THFR2 | Thunbergia fragrans Roxb. | whitelady | Acanthaceae
|
| THGR3 | Thunbergia grandiflora Roxb. | Bengal trumpet | Acanthaceae
|
| THLA6 | Thunbergia laurifolia Lindl. | laurel clockvine | Acanthaceae
|
| THVO | Thunbergia volubilis Pers. | Thunbergia fragrans | Acanthaceae
|
| THUNB | Thunbergia Retz. | thunbergia | Acanthaceae
|
| THTH4 | Thurberia thespesioides Gray | Gossypium thurberi | Malvaceae
|
| THTR7 | Thurovia triflora Rose | threeflower snakeweed | Asteraceae
|
| THURO2 | Thurovia Rose | thurovia | Asteraceae
|
| THPO9 | Thyana portoricensis (Radlk.) Britt. | Thouinia striata var. portoricensis | Sapindaceae
|
| THST4 | Thyana striata (Radlk.) Britt. | Thouinia striata var. striata | Sapindaceae
|
| THTA | Thyella tamnifolia (L.) Raf. | Jacquemontia tamnifolia | Convolvulaceae
|
| THPA7 | Thymelaea passerina (L.) Coss. & Germ. | mezereon | Thymelaeaceae
|
| THYME | Thymelaea P. Mill. | thymelaea | Thymelaeaceae
|
| THAC | Thymophylla acerosa (DC.) Strother | pricklyleaf dogweed | Asteraceae
|
| THAUA | Thymophylla aurea (Gray) Greene ex Britt. var. aurea | manyawn pricklyleaf | Asteraceae
|
| THAUP | Thymophylla aurea (Gray) Greene ex Britt. var. polychaeta (Gray) Strother | manyawn pricklyleaf | Asteraceae
|
| THAU4 | Thymophylla aurea (Gray) Greene ex Britt. | manyawn pricklyleaf | Asteraceae
|
| THCO10 | Thymophylla concinna (Gray) Strother | Sonoran pricklyleaf | Asteraceae
|
| THMI7 | Thymophylla micropoides (DC.) Strother | woolly pricklyleaf | Asteraceae
|
| THPEB | Thymophylla pentachaeta (DC.) Small var. belenidium (DC.) Strother | fiveneedle pricklyleaf | Asteraceae
|
| THPEH | Thymophylla pentachaeta (DC.) Small var. hartwegii (Gray) Strother | Hartweg's pricklyleaf | Asteraceae
|
| THPEP | Thymophylla pentachaeta (DC.) Small var. pentachaeta | fiveneedle pricklyleaf | Asteraceae
|
| THPEP2 | Thymophylla pentachaeta (DC.) Small var. puberula (Rydb.) Strother | fiveneedle pricklyleaf | Asteraceae
|
| THPE4 | Thymophylla pentachaeta (DC.) Small | fiveneedle pricklyleaf | Asteraceae
|
| THPO10 | Thymophylla polychaeta Gray | Thymophylla aurea var. polychaeta | Asteraceae
|
| THSER | Thymophylla setifolia Lag. var. radiata (Gray) Strother | Texas pricklyleaf | Asteraceae
|
| THSE4 | Thymophylla setifolia Lag. | Texas pricklyleaf | Asteraceae
|
| THTET | Thymophylla tenuiloba (DC.) Small var. tenuiloba | bristleleaf pricklyleaf | Asteraceae
|
| THTET2 | Thymophylla tenuiloba (DC.) Small var. texana (Cory) Strother | Texas bristleleaf | Asteraceae
|
| THTET3 | Thymophylla tenuiloba (DC.) Small var. treculii (Gray) Strother | Trecul's pricklyleaf | Asteraceae
|
| THTEW | Thymophylla tenuiloba (DC.) Small var. wrightii (Gray) Strother | Wright's pricklyleaf | Asteraceae
|
| THTE7 | Thymophylla tenuiloba (DC.) Small | bristleleaf pricklyleaf | Asteraceae
|
| THTE8 | Thymophylla tephroleuca (Blake) Strother | ashy pricklyleaf | Asteraceae
|
| THYMO | Thymophylla Lag. | pricklyleaf | Asteraceae
|
| THAR8 | Thymus arcticus (Dur.) Ronniger | Thymus praecox ssp. arcticus | Lamiaceae
|
| THCA10 | Thymus capitatus (L.) Hoffsgg. & Link | thymus | Lamiaceae
|
| THMA11 | Thymus marschallianus Willd. | Thymus pannonicus | Lamiaceae
|
| THPA11 | Thymus pannonicus All. | Eurasian thyme | Lamiaceae
|
| THPRA | Thymus praecox Opiz ssp. arcticus (Dur.) Jalas | creeping thyme | Lamiaceae
|
| THPR | Thymus praecox Opiz | mother of thyme | Lamiaceae
|
| THPU5 | Thymus pulegioides L. | lemon thyme | Lamiaceae
|
| THSEC | Thymus serpyllum L. ssp. chamaedrys (Fries) Voll. | Thymus pulegioides | Lamiaceae
|
| THSEA | Thymus serpyllum L. var. albus hort. | Thymus pulegioides | Lamiaceae
|
| THSE | Thymus serpyllum auct. non L. | Thymus praecox ssp. arcticus | Lamiaceae
|
| THVU | Thymus vulgaris L. | garden thyme | Lamiaceae
|
| THYMU | Thymus L. | thyme | Lamiaceae
|
| THCO12 | Thyrea confusa Henssen | | Lichinaceae
|