| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| SPGR5 | Spiranthes graminea Lindl. | Canelo ladies'-tresses | Orchidaceae
|
| SPGR6 | Spiranthes grayi Ames | Spiranthes tuberosa | Orchidaceae
|
| SPIN7 | Spiranthes infernalis Sheviak | Ash Meadows ladies'-tresses | Orchidaceae
|
| SPIN6 | Spiranthes �intermedia Ames | | Orchidaceae
|
| SPIN11 | Spiranthes �intermedia auct. non Ames | Spiranthes casei | Orchidaceae
|
| SPLAG | Spiranthes lacera (Raf.) Raf. var. gracilis (Bigelow) Luer | northern slender ladies'-tresses | Orchidaceae
|
| SPLAL | Spiranthes lacera (Raf.) Raf. var. lacera | northern slender ladies'-tresses | Orchidaceae
|
| SPLA4 | Spiranthes lacera (Raf.) Raf. | northern slender ladies'-tresses | Orchidaceae
|
| SPLA3 | Spiranthes laciniata (Small) Ames | lacelip ladies'-tresses | Orchidaceae
|
| SPLAP | Spiranthes lanceolata (Aubl.) L�on var. paludicola Luer | Stenorrhynchos lanceolatum var. paludicola | Orchidaceae
|
| SPLA5 | Spiranthes lanceolata (Aubl.) L�on | Stenorrhynchos lanceolatum var. lanceolatum | Orchidaceae
|
| SPLI3 | Spiranthes lineata Lindl. | Hapalorchis lineatus | Orchidaceae
|
| SPLO2 | Spiranthes longilabris Lindl. | giantspiral ladies'-tresses | Orchidaceae
|
| SPLU3 | Spiranthes lucayana (Britt.) Cogn. | Mesadenus polyanthus | Orchidaceae
|
| SPLU2 | Spiranthes lucida (H.H. Eat.) Ames | shining ladies'-tresses | Orchidaceae
|
| SPMA5 | Spiranthes magnicamporum Sheviak | Great Plains ladies'-tresses | Orchidaceae
|
| SPMI2 | Spiranthes michuacana (Llave & Lex.) Hemsl. | Stenorrhynchos michuacanus | Orchidaceae
|
| SPOC | Spiranthes ochroleuca (Rydb.) Rydb. | yellow nodding ladies'-tresses | Orchidaceae
|
| SPOD | Spiranthes odorata (Nutt.) Lindl. | marsh ladies'-tresses | Orchidaceae
|
| SPOR2 | Spiranthes orchioides (Sw.) A. Rich. | Stenorrhynchos lanceolatum var. lanceolatum | Orchidaceae
|
| SPOVE | Spiranthes ovalis Lindl. var. erostellata Catling | October ladies'-tresses | Orchidaceae
|
| SPOVO | Spiranthes ovalis Lindl. var. ovalis | October ladies'-tresses | Orchidaceae
|
| SPOV | Spiranthes ovalis Lindl. | October ladies'-tresses | Orchidaceae
|
| SPPA4 | Spiranthes parasitica A. Rich. & Gal. | parasitic ladies'-tresses | Orchidaceae
|
| SPPA5 | Spiranthes parksii Correll | Navasota ladies'-tresses | Orchidaceae
|
| SPPO3 | Spiranthes polyantha Reichenb. f. | Mesadenus polyanthus | Orchidaceae
|
| SPPO7 | Spiranthes porrifolia Lindl. | creamy ladies'-tresses | Orchidaceae
|
| SPPR2 | Spiranthes praecox (Walt.) S. Wats. | greenvein ladies'-tresses | Orchidaceae
|
| SPROD | Spiranthes romanzoffiana Cham. var. diluvialis (Sheviak) Welsh | Spiranthes diluvialis | Orchidaceae
|
| SPROP | Spiranthes romanzoffiana Cham. var. porrifolia (Lindl.) Ames & Correll | Spiranthes porrifolia | Orchidaceae
|
| SPRO | Spiranthes romanzoffiana Cham. | hooded ladies'-tresses | Orchidaceae
|
| SPSI6 | Spiranthes �simpsonii Catling & Sheviak | | Orchidaceae
|
| SPSP3 | Spiranthes speciosa (Jacq.) A. Rich. | Stenorrhynchos speciosus | Orchidaceae
|
| SPST2 | Spiranthes �steigeri Correll | Spiranthes ochroleuca | Orchidaceae
|
| SPST6 | Spiranthes stricta Rydb. | Spiranthes romanzoffiana | Orchidaceae
|
| SPTO5 | Spiranthes torta (Thunb.) Garay & Sweet | southern ladies'-tresses | Orchidaceae
|
| SPTO3 | Spiranthes tortilis (Sw.) L.C. Rich. | Spiranthes torta | Orchidaceae
|
| SPTUG | Spiranthes tuberosa Raf. var. grayi (Ames) Fern. | Spiranthes tuberosa | Orchidaceae
|
| SPTU | Spiranthes tuberosa Raf. | little ladies'-tresses | Orchidaceae
|
| SPUN | Spiranthes unalascensis Spreng. | Piperia unalascensis | Orchidaceae
|
| SPVE | Spiranthes vernalis Engelm. & Gray | spring ladies'-tresses | Orchidaceae
|
| SPIRA2 | Spiranthes L.C. Rich. | ladies'-tresses | Orchidaceae
|
| SPIN8 | Spirodela intermedia Koch | intermediate duckweed | Lemnaceae
|
| SPOL2 | Spirodela oligorrhiza (Kurz) Hegelm. | Spirodela punctata | Lemnaceae
|
| SPPO8 | Spirodela polyrhiza (L.) Schleiden | giant duckweed | Lemnaceae
|
| SPPOM | Spirodela polyrrhiza (L.) Schleid. var. masonii Daubs | Spirodela polyrrhiza | Lemnaceae
|
| SPPO | Spirodela polyrrhiza (L.) Schleid. | common duckmeat | Lemnaceae
|
| SPPU4 | Spirodela punctata (G.F.W. Mey.) C.H. Thompson | dotted duckmeat | Lemnaceae
|
| SPIRO | Spirodela Schleid. | duckmeat | Lemnaceae
|
| SPFR | Spironema fragrans Lindl. | Callisia fragrans | Commelinaceae
|
| SPRO2 | Spironema robbinsii Sanvalle | Callisia repens | Commelinaceae
|
| SPBE5 | Splachnobryum bernoullii C. M�ll. | Splachnobryum obtusum | Splachnobryaceae
|
| SPKI | Splachnobryum kieneri Williams | Bryum turbinatum | Bryaceae
|
| SPOB2 | Splachnobryum obtusum (Brid.) C. M�ll. | splachnobryum moss | Splachnobryaceae
|
| SPLAC2 | Splachnobryum C. M�ll. | splachnobryum moss | Splachnobryaceae
|
| SPAM5 | Splachnum ampullaceum Hedw. | small capsule dung moss | Splachnaceae
|
| SPHE5 | Splachnum heterophyllum Drumm. | Splachnum vasculosum var. heterophyllum | Splachnaceae
|
| SPLUL | Splachnum luteum Hedw. var. luteum | yellow moosedung moss | Splachnaceae
|
| SPLUM | Splachnum luteum Hedw. var. melanocaulon Wahlenb. | dark yellow moosedung moss | Splachnaceae
|
| SPLU7 | Splachnum luteum Hedw. | yellow moosedung moss | Splachnaceae
|
| SPME4 | Splachnum melanocaulon (Wahlenb.) Schwaegr. | Splachnum luteum var. melanocaulon | Splachnaceae
|
| SPOV2 | Splachnum ovatum Dicks. ex Hedw. | Splachnum sphaericum | Splachnaceae
|
| SPPE6 | Splachnum pennsylvanicum (Brid.) Grout ex Crum | Pennsylvania dung moss | Splachnaceae
|
| SPRU70 | Splachnum rubrum Hedw. | brilliant red dung moss | Splachnaceae
|
| SPSP70 | Splachnum sphaericum Hedw. | pinkstink dung moss | Splachnaceae
|
| SPVAH | Splachnum vasculosum Hedw. var. heterophyllum (Drumm.) Brass. | oddleaf dung moss | Splachnaceae
|
| SPVAV | Splachnum vasculosum Hedw. var. vasculosum | splachnum dung moss | Splachnaceae
|
| SPVA3 | Splachnum vasculosum Hedw. | splachnum dung moss | Splachnaceae
|
| SPLAC | Splachnum Hedw. | splachnum dung moss | Splachnaceae
|
| SPCY2 | Spondias cytherea Sonnerat | Spondias dulcis | Anacardiaceae
|
| SPDU3 | Spondias dulcis Parkinson | Jewish plum | Anacardiaceae
|
| SPLU6 | Spondias lutea L. | Spondias mombin | Anacardiaceae
|
| SPMO | Spondias mombin L. | yellow mombin | Anacardiaceae
|
| SPPU | Spondias purpurea L. | purple mombin | Anacardiaceae
|
| SPTU5 | Spondias tuberosa Arruda ex Koster | imbu | Anacardiaceae
|
| SPOND | Spondias L. | mombin | Anacardiaceae
|
| SPCI2 | Sporastatia cinerea (Schaerer) Korber | Sporastatia polyspora | Acarosporaceae
|
| SPPO5 | Sporastatia polyspora (Nyl.) Grummann | | Acarosporaceae
|
| SPTE10 | Sporastatia testudinea (Ach.) A. Massal. | | Acarosporaceae
|
| SPORA | Sporastatia A. Massal. | sporastatia | Acarosporaceae
|
| SPAF | Sporobolus africanus (Poir.) Robyns & Tournay | Sporobolus indicus var. capensis | Poaceae
|
| SPAIW | Sporobolus airoides (Torr.) Torr. var. wrightii (Munro ex Scribn.) Gould | Sporobolus wrightii | Poaceae
|
| SPAI | Sporobolus airoides (Torr.) Torr. | alkali sacaton | Poaceae
|
| SPAN6 | Sporobolus angustus Buckl. | Sporobolus indicus var. indicus | Poaceae
|
| SPAR3 | Sporobolus argutus (Nees) Kunth | Sporobolus coromandelianus | Poaceae
|
| SPASC | Sporobolus asper (Michx.) Kunth var. canovirens (Nash) Shinners | Sporobolus clandestinus | Poaceae
|
| SPASC2 | Sporobolus asper (Michx.) Kunth var. clandestinus (Biehler) Shinners | Sporobolus clandestinus | Poaceae
|
| SPASD | Sporobolus asper (Michx.) Kunth var. drummondii (Trin.) Vasey | Sporobolus compositus var. drummondii | Poaceae
|
| SPASH | Sporobolus asper (Michx.) Kunth var. hookeri (Trin.) Vasey | Sporobolus compositus var. compositus | Poaceae
|
| SPASM | Sporobolus asper (Michx.) Kunth var. macer (Trin.) Shinners | Sporobolus compositus var. macer | Poaceae
|
| SPASP | Sporobolus asper (Michx.) Kunth var. pilosus (Vasey) A.S. Hitchc. | Sporobolus compositus var. drummondii | Poaceae
|
| SPAS | Sporobolus asper (Michx.) Kunth | Sporobolus compositus var. compositus | Poaceae
|
| SPAS3 | Sporobolus asperifolius (Nees & Meyen ex Trin.) Nees | Muhlenbergia asperifolia | Poaceae
|
| SPAT2 | Sporobolus attenuatus Nash | Sporobolus compositus var. drummondii | Poaceae
|
| SPBE4 | Sporobolus berterianus (Trin.) A.S. Hitchc. & Chase | Sporobolus indicus var. indicus | Poaceae
|
| SPBU | Sporobolus buckleyi Vasey | Buckley's dropseed | Poaceae
|
| SPCA12 | Sporobolus canovirens Nash | Sporobolus clandestinus | Poaceae
|
| SPCLC | Sporobolus clandestinus (Biehler) A.S. Hitchc. var. canovirens (Nash) Steyermark & Kucera | Sporobolus clandestinus | Poaceae
|
| SPCL | Sporobolus clandestinus (Biehler) A.S. Hitchc. | rough dropseed | Poaceae
|
| SPCOC3 | Sporobolus compositus (Poir.) Merr. var. clandestinus (Biehler) J. Wipff & S.D. Jones | Sporobolus clandestinus | Poaceae
|
| SPCOC2 | Sporobolus compositus (Poir.) Merr. var. compositus | composite dropseed | Poaceae
|