| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| SEDES2 | Selaginella densa Rydb. var. standleyi (Maxon) R. Tryon | Standley's spikemoss | Selaginellaceae
|
| SEDE2 | Selaginella densa Rydb. | lesser spikemoss | Selaginellaceae
|
| SEDO | Selaginella douglasii (Hook. & Grev.) Spring | Douglas' spikemoss | Selaginellaceae
|
| SEEA | Selaginella eatonii Hieron. ex Small | Eaton's spikemoss | Selaginellaceae
|
| SEEC | Selaginella eclipes Buck | hidden spikemoss | Selaginellaceae
|
| SEENS | Selaginella engelmannii Hieron. var. scopulorum (Maxon) C.F. Reed | Selaginella densa var. scopulorum | Selaginellaceae
|
| SEENS2 | Selaginella engelmannii Hieron. var. standleyi (Maxon) C.F. Reed | Selaginella densa var. standleyi | Selaginellaceae
|
| SEEN | Selaginella engelmannii Hieron. | Selaginella densa var. densa | Selaginellaceae
|
| SEER | Selaginella eremophila Maxon | desert spikemoss | Selaginellaceae
|
| SEFL2 | Selaginella flabellata (L.) Spring | fan spikemoss | Selaginellaceae
|
| SEHA2 | Selaginella hansenii Hieron. | Hansen's spikemoss | Selaginellaceae
|
| SEKR | Selaginella kraussiana (Kunze) A. Braun | Krauss' spikemoss | Selaginellaceae
|
| SEKR2 | Selaginella krugii Hieron. | Krug's spikemoss | Selaginellaceae
|
| SELA5 | Selaginella laxifolia Baker | limpleaf spikemoss | Selaginellaceae
|
| SELE2 | Selaginella lepidophylla (Hook. & Grev.) Spring | flower of stone | Selaginellaceae
|
| SELE3 | Selaginella leucobryoides Maxon | Mojave spikemoss | Selaginellaceae
|
| SELU3 | Selaginella ludoviciana (A. Braun) A. Braun | gulf spikemoss | Selaginellaceae
|
| SEME2 | Selaginella menziesii (Hook. & Grev.) Spring | Menzies' spikemoss | Selaginellaceae
|
| SEMUL | Selaginella mutica D.C. Eat. ex Underwood var. limitanea Weatherby | bluntleaf spikemoss | Selaginellaceae
|
| SEMUM | Selaginella mutica D.C. Eat. ex Underwood var. mutica | bluntleaf spikemoss | Selaginellaceae
|
| SEMUT | Selaginella mutica D.C. Eat. ex Underwood var. texana Weatherby | Selaginella mutica var. limitanea | Selaginellaceae
|
| SEMU | Selaginella mutica D.C. Eat. ex Underwood | bluntleaf spikemoss | Selaginellaceae
|
| SENE3 | Selaginella �neomexicana Maxon (pro sp.) | | Selaginellaceae
|
| SEOR3 | Selaginella oregana D.C. Eat. | Oregon spikemoss | Selaginellaceae
|
| SEOV | Selaginella ovifolia Baker | oval-leaf spikemoss | Selaginellaceae
|
| SEPA11 | Selaginella parvula Hbd. | Selaginella sandvicensis | Selaginellaceae
|
| SEPE | Selaginella peruviana (Milde) Hieron. | Peruvian spikemoss | Selaginellaceae
|
| SEPIP | Selaginella pilifera A. Braun var. pringlei (Baker) Morton | Selaginella pilifera | Selaginellaceae
|
| SEPI | Selaginella pilifera A. Braun | resurrection plant | Selaginellaceae
|
| SEPL4 | Selaginella plagiochila sensu Krug & Urban, non Baker | Selaginella armata | Selaginellaceae
|
| SEPL3 | Selaginella plana (Desv. ex Poir.) Hieron. | Asian spikemoss | Selaginellaceae
|
| SEPL2 | Selaginella plumosa (L.) K. Presl | plumed spikemoss | Selaginellaceae
|
| SEPO6 | Selaginella portoricensis A. Braun | Selaginella substipitata | Selaginellaceae
|
| SERI3 | Selaginella riddellii Van Eselt. | Selaginella arenicola ssp. riddellii | Selaginellaceae
|
| SERU | Selaginella rupestris (L.) Spring | northern selaginella | Selaginellaceae
|
| SERU2 | Selaginella rupincola Underwood | rockloving spikemoss | Selaginellaceae
|
| SESA2 | Selaginella sandvicensis Baker | Hawai'i spikemoss | Selaginellaceae
|
| SESC5 | Selaginella scopulorum Maxon | Selaginella densa var. scopulorum | Selaginellaceae
|
| SESE | Selaginella selaginoides (L.) Beauv. ex Mart. & Schrank | club spikemoss | Selaginellaceae
|
| SESH2 | Selaginella sheldonii Maxon | Selaginella peruviana | Selaginellaceae
|
| SESI | Selaginella sibirica (Milde) Hieron. | Siberian spikemoss | Selaginellaceae
|
| SESI4 | Selaginella sintenisii Hieron. | Selaginella subcaulescens | Selaginellaceae
|
| SEST5 | Selaginella standleyi Maxon | Selaginella densa var. standleyi | Selaginellaceae
|
| SEST7 | Selaginella stolonifera (Sw.) Spring | Selaginella plumosa | Selaginellaceae
|
| SESU2 | Selaginella subcaulescens Baker | handsome spikemoss | Selaginellaceae
|
| SESU3 | Selaginella substipitata Spring | stalked spikemoss | Selaginellaceae
|
| SETE8 | Selaginella tenella (Beauv.) Spring | delicate spikemoss | Selaginellaceae
|
| SETO | Selaginella tortipila A. Braun | twistedhair spikemoss | Selaginellaceae
|
| SEUN2 | Selaginella uncinata (Desv. ex Poir.) Spring | blue spikemoss | Selaginellaceae
|
| SEUND | Selaginella underwoodii Hieron. var. dolichotricha Weatherby | Selaginella underwoodii | Selaginellaceae
|
| SEUN | Selaginella underwoodii Hieron. | Underwood's spikemoss | Selaginellaceae
|
| SEUT | Selaginella utahensis Flowers | Utah spikemoss | Selaginellaceae
|
| SEVI | Selaginella viridissima Weatherby | green spikemoss | Selaginellaceae
|
| SEWA | Selaginella wallacei Hieron. | Wallace's spikemoss | Selaginellaceae
|
| SEWA2 | Selaginella watsonii Underwood | Watson's spikemoss | Selaginellaceae
|
| SEWE3 | Selaginella weatherbiana R. Tryon | Weatherby's spikemoss | Selaginellaceae
|
| SEWI | Selaginella willdenowii (Desv. ex Poir.) Baker | Willdenow's spikemoss | Selaginellaceae
|
| SEWR2 | Selaginella wrightii Hieron. | Wright's spikemoss | Selaginellaceae
|
| SELAG | Selaginella Beauv. | spikemoss | Selaginellaceae
|
| SEAP4 | Selenia aptera (S. Wats.) Small | Selenia aurea | Brassicaceae
|
| SEAU | Selenia aurea Nutt. | golden selenia | Brassicaceae
|
| SEDI2 | Selenia dissecta Torr. & Gray | Texas selenia | Brassicaceae
|
| SEGR2 | Selenia grandis R.F. Martin | large selenia | Brassicaceae
|
| SEJOJ | Selenia jonesii Cory var. jonesii | Jones' selenia | Brassicaceae
|
| SEJOO | Selenia jonesii Cory var. obovata Rollins | Jones' selenia | Brassicaceae
|
| SEJO | Selenia jonesii Cory | Jones' selenia | Brassicaceae
|
| SELEN | Selenia Nutt. | selenia | Brassicaceae
|
| SECO16 | Selenicereus coniflorus (Weingart) Britt. & Rose | coneflower moonlight cactus | Cactaceae
|
| SEGR10 | Selenicereus grandiflorus (L.) Britt. & Rose | queen of the night | Cactaceae
|
| SEPT | Selenicereus pteranthus (Link ex A. Dietr.) Britt. & Rose | princess of the night | Cactaceae
|
| SESP8 | Selenicereus spinulosus (DC.) Britt. & Rose | vinelike moonlight cactus | Cactaceae
|
| SELEN2 | Selenicereus (Berger) Britt. & Rose | moonlight cactus | Cactaceae
|
| SEAC8 | Seligeria acutifolia Lindb. in Hartm. | acuteleaf small limestone moss | Seligeriaceae
|
| SEBR5 | Seligeria brevifolia (Lindb.) Lindb. | shortleaf small limestone moss | Seligeriaceae
|
| SECA15 | Seligeria calcarea (Hedw.) Bruch & Schimp. in B.S.G. | small limestone moss | Seligeriaceae
|
| SECA16 | Seligeria campylopoda Kindb. in Mac. & Kindb. | small limestone moss | Seligeriaceae
|
| SECA17 | Seligeria careyana Vitt & Schof. | Carey small limestone moss | Seligeriaceae
|
| SEDI12 | Seligeria diversifolia Lindb. | diverseleaf small limestone moss | Seligeriaceae
|
| SEDO4 | Seligeria donniana (Sm.) C. M�ll. | Donn's small limestone moss | Seligeriaceae
|
| SEDO5 | Seligeria donnii Lindb. | Seligeria donniana | Seligeriaceae
|
| SEOE | Seligeria oelandica C. Jens. & Medel. | small limestone moss | Seligeriaceae
|
| SEPO7 | Seligeria polaris Berggr. | northern small limestone moss | Seligeriaceae
|
| SEPU14 | Seligeria pusilla (Hedw.) Bruch & Schimp. in B.S.G. | small limestone moss | Seligeriaceae
|
| SERE6 | Seligeria recurvata (Hedw.) Bruch & Schimp. in B.S.G. | recurved small limestone moss | Seligeriaceae
|
| SESU70 | Seligeria subimmersa Lindb. | small limestone moss | Seligeriaceae
|
| SETR7 | Seligeria tristichoides Kindb. | small limestone moss | Seligeriaceae
|
| SELIG2 | Seligeria Bruch & Schimp. in B.S.G. | small limestone moss | Seligeriaceae
|
| SEAN | Selinocarpus angustifolius Torr. | narrowleaf moonpod | Nyctaginaceae
|
| SECH3 | Selinocarpus chenopodioides Gray | Ammocodon chenopodioides | Nyctaginaceae
|
| SEDIN | Selinocarpus diffusus Gray ssp. nevadensis Standl. | Selinocarpus nevadensis | Nyctaginaceae
|
| SEDI3 | Selinocarpus diffusus Gray | spreading moonpod | Nyctaginaceae
|
| SELA3 | Selinocarpus lanceolatus Woot. | lanceleaf moonpod | Nyctaginaceae
|
| SEMA17 | Selinocarpus maloneanus B.L. Turner | gypsum moonpod | Nyctaginaceae
|
| SENE5 | Selinocarpus nevadensis (Standl.) Fowler & Turner | desert moonpod | Nyctaginaceae
|
| SEPA | Selinocarpus parvifolius (Torr.) Standl. | littleleaf moonpod | Nyctaginaceae
|
| SELIN | Selinocarpus Gray | moonpod | Nyctaginaceae
|
| SECA20 | Selinum carvifolia (L.) L. | | Apiaceae
|
| SEMO7 | Selinum monnieri L. | Cnidium monnieri | Apiaceae
|
| SELIN2 | Selinum L. | selinum | Apiaceae
|
| SEGL7 | Selloa glutinosa Spreng. | Gymnosperma glutinosum | Asteraceae
|
| SEAD3 | Sematophyllum adnatum (Michx.) Britt. | sematophyllum moss | Sematophyllaceae
|