| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| COHO2 | Conostegia hotteana Urban & Ekman | Conostegia rufescens | Melastomataceae
|
| COPU5 | Conostegia puberula Naud. | Conostegia rufescens | Melastomataceae
|
| CORU17 | Conostegia rufescens Naud. | Luquillo Mountain snailwood | Melastomataceae
|
| CONOS | Conostegia D. Don | snailwood | Melastomataceae
|
| COBO6 | Conostomum boreale Sw. | Conostomum tetragonum | Bartramiaceae
|
| COTE70 | Conostomum tetragonum (Hedw.) Lindb. | conostomum moss | Bartramiaceae
|
| CONOS2 | Conostomum Sw. in Web. & Mohr | conostomum moss | Bartramiaceae
|
| COAL12 | Conotrema albonigrum Zahlbr. | Ocellularia stictidea | Thelotremataceae
|
| COUR2 | Conotrema urceolatum (Ach.) Tuck. | | Stictidaceae
|
| CONOT | Conotrema Tuck. | conotrema | Stictidaceae
|
| COBR5 | Conradina brevifolia Shinners | Conradina canescens | Lamiaceae
|
| COCA19 | Conradina canescens Gray | false rosemary | Lamiaceae
|
| COET | Conradina etonia Kral & McCartney | Eton rosemary | Lamiaceae
|
| COGL9 | Conradina glabra Shinners | Apalachicola false rosemary | Lamiaceae
|
| COGR8 | Conradina grandiflora Small | largeflower false rosemary | Lamiaceae
|
| COMO7 | Conradina montana Small | Conradina verticillata | Lamiaceae
|
| COPU7 | Conradina puberula Small | Conradina canescens | Lamiaceae
|
| COVE4 | Conradina verticillata Jennison | Cumberland false rosemary | Lamiaceae
|
| CONRA | Conradina Gray | false rosemary | Lamiaceae
|
| COOR | Conringia orientalis (L.) Dumort. | hare's ear mustard | Brassicaceae
|
| CONRI | Conringia Heister ex Fabr. | hare's ear mustard | Brassicaceae
|
| COCO14 | Consolea corallicola Small | Opuntia spinosissima | Cactaceae
|
| COMO8 | Consolea moniliformis (L.) Britt. | Opuntia moniliformis | Cactaceae
|
| CORU8 | Consolea rubescens (Salm-Dyck ex DC.) Lem. | Opuntia rubescens | Cactaceae
|
| COAJ | Consolida ajacis (L.) Schur | doubtful knight's-spur | Ranunculaceae
|
| COAM4 | Consolida ambigua (L.) P.W. Ball & Heywood | Consolida ajacis | Ranunculaceae
|
| COOR4 | Consolida orientalis (J. Gay) Schroedinger | oriental knight's-spur | Ranunculaceae
|
| COPU21 | Consolida pubescens (DC.) So� | | Ranunculaceae
|
| CORE2 | Consolida regalis S.F. Gray | royal knight's-spur | Ranunculaceae
|
| COTE19 | Consolida tenuissima (Sibthorp & Sm.) So� | | Ranunculaceae
|
| CONSO | Consolida S.F. Gray | knight's-spur | Ranunculaceae
|
| COBI10 | Convallaria biflora Walt. p.p. | Polygonatum biflorum var. commutatum | Liliaceae
|
| COFR6 | Convallaria fruticosa L. | Cordyline fruticosa | Liliaceae
|
| COMAM | Convallaria majalis L. var. montana (Raf.) Ahles | Convallaria majuscula | Liliaceae
|
| COMA7 | Convallaria majalis L. | European lily of the valley | Liliaceae
|
| COMA19 | Convallaria majuscula Greene | American lily of the valley | Liliaceae
|
| COMO4 | Convallaria montana Raf. | Convallaria majuscula | Liliaceae
|
| COPU13 | Convallaria pubescens Willd. | Polygonatum pubescens | Liliaceae
|
| CORA10 | Convallaria racemosa L. | Maianthemum racemosum ssp. racemosum | Liliaceae
|
| COST12 | Convallaria stellata L. | Maianthemum stellatum | Liliaceae
|
| COTR11 | Convallaria trifolia L. | Maianthemum trifolium | Liliaceae
|
| CONVA | Convallaria L. | lily of the valley | Liliaceae
|
| COAL4 | Convolvulus althaeoides L. | mallow bindweed | Convolvulaceae
|
| COAM10 | Convolvulus ambigens House | Convolvulus arvensis | Convolvulaceae
|
| COAM9 | Convolvulus americanus (Sims) Greene | Calystegia sepium ssp. americana | Convolvulaceae
|
| COARI | Convolvulus aridus Greene ssp. intermedius Abrams | Calystegia macrostegia ssp. intermedia | Convolvulaceae
|
| COARL | Convolvulus aridus Greene ssp. longilobus Abrams | Calystegia macrostegia ssp. intermedia | Convolvulaceae
|
| COART | Convolvulus aridus Greene ssp. tenuifolius Abrams | Calystegia macrostegia ssp. tenuifolia | Convolvulaceae
|
| COAR11 | Convolvulus aridus Greene | Calystegia macrostegia ssp. arida | Convolvulaceae
|
| COAR4 | Convolvulus arvensis L. | field bindweed | Convolvulaceae
|
| COBA5 | Convolvulus batatas L. | Ipomoea batatas | Convolvulaceae
|
| COBI6 | Convolvulus binghamiae Greene | Calystegia sepium ssp. binghamiae | Convolvulaceae
|
| COCA28 | Convolvulus capillaceus Kunth | Ipomoea capillacea | Convolvulaceae
|
| COCA24 | Convolvulus carolinus L. | Ipomoea cordatotriloba var. cordatotriloba | Convolvulaceae
|
| COCO16 | Convolvulus corymbosus L. | Turbina corymbosa | Convolvulaceae
|
| COCY5 | Convolvulus cyclostegius House | Calystegia macrostegia ssp. cyclostegia | Convolvulaceae
|
| CODI9 | Convolvulus dissectus Jacq. | Merremia dissecta | Convolvulaceae
|
| COEQ | Convolvulus equitans Benth. | Texas bindweed | Convolvulaceae
|
| COER9 | Convolvulus erubescens Sims | | Convolvulaceae
|
| COFR7 | Convolvulus fraterniflorus (Mackenzie & Bush) Mackenzie & Bush | Calystegia silvatica ssp. fraterniflora | Convolvulaceae
|
| COFUB | Convolvulus fulcratus (Gray) Greene var. berryi (Eastw.) Jepson | Calystegia malacophylla ssp. malacophylla var. berryi | Convolvulaceae
|
| COFUD | Convolvulus fulcratus (Gray) Greene var. deltoideus (Greene) Jepson | Calystegia occidentalis ssp. occidentalis var. tomentella | Convolvulaceae
|
| COFU2 | Convolvulus fulcratus (Gray) Greene | Calystegia occidentalis ssp. fulcrata | Convolvulaceae
|
| COHE10 | Convolvulus hederaceus L. | Ipomoea nil | Convolvulaceae
|
| COHE9 | Convolvulus hermannioides Gray | Convolvulus equitans | Convolvulaceae
|
| COIN7 | Convolvulus incanus auct. non Vahl | Convolvulus arvensis | Convolvulaceae
|
| COIN9 | Convolvulus interior House | Calystegia macounii | Convolvulaceae
|
| COJA2 | Convolvulus japonicus Thunb. | Calystegia pellita | Convolvulaceae
|
| COLI11 | Convolvulus linearilobus Eastw. | Calystegia longipes | Convolvulaceae
|
| COLO5 | Convolvulus longipes S. Wats. | Calystegia longipes | Convolvulaceae
|
| COLUF | Convolvulus luteolus Gray var. fulcratus Gray | Calystegia occidentalis ssp. fulcrata | Convolvulaceae
|
| COMA8 | Convolvulus macrostegius Greene | Calystegia macrostegia ssp. macrostegia | Convolvulaceae
|
| COMAC2 | Convolvulus malacophyllus Greene ssp. collinus (Greene) Abrams | Calystegia collina ssp. collina | Convolvulaceae
|
| COMAP3 | Convolvulus malacophyllus Greene ssp. pedicellatus (Jepson) Abrams | Calystegia malacophylla ssp. pedicellata | Convolvulaceae
|
| COMA9 | Convolvulus malacophyllus Greene | Calystegia malacophylla ssp. malacophylla var. malacophylla | Convolvulaceae
|
| COME9 | Convolvulus meyeri Spreng. | Ipomoea meyeri | Convolvulaceae
|
| COMU3 | Convolvulus muricatus L. | Ipomoea turbinata | Convolvulaceae
|
| CONA2 | Convolvulus nashii House | Calystegia sepium ssp. sepium | Convolvulaceae
|
| CONE3 | Convolvulus nervosus Burm. f. | Argyreia nervosa | Convolvulaceae
|
| CONI6 | Convolvulus nil L. | Ipomoea nil | Convolvulaceae
|
| CONO | Convolvulus nodiflorus Desv. | aguinaldo blanco | Convolvulaceae
|
| CONU8 | Convolvulus nummularius L. | Evolvulus nummularius | Convolvulaceae
|
| CONY | Convolvulus nyctagineus Greene | Calystegia atriplicifolia ssp. atriplicifolia | Convolvulaceae
|
| COOCF | Convolvulus occidentalis Gray ssp. fruticetorus (Greene) Abrams | Calystegia occidentalis ssp. occidentalis var. occidentalis | Convolvulaceae
|
| COOCP | Convolvulus occidentalis Gray var. purpuratus (Greene) J.T. Howell | Calystegia purpurata ssp. purpurata | Convolvulaceae
|
| COOCS3 | Convolvulus occidentalis Gray var. saxicola (Eastw.) J.T. Howell | Calystegia purpurata ssp. saxicola | Convolvulaceae
|
| COOCS2 | Convolvulus occidentalis Gray var. solanensis (Jepson) J.T. Howell | Calystegia purpurata ssp. solanensis | Convolvulaceae
|
| COOC5 | Convolvulus occidentalis Gray | Calystegia occidentalis ssp. occidentalis var. occidentalis | Convolvulaceae
|
| COPE4 | Convolvulus peirsonii Abrams | Calystegia peirsonii | Convolvulaceae
|
| COPE3 | Convolvulus pellitus Ledeb. | Calystegia pellita | Convolvulaceae
|
| COPE5 | Convolvulus pes-caprae L. | Ipomoea pes-caprae ssp. brasiliensis | Convolvulaceae
|
| COPI7 | Convolvulus pilosellifolius Desr. | soft bindweed | Convolvulaceae
|
| COPO | Convolvulus polymorphus Greene | Calystegia occidentalis ssp. occidentalis var. occidentalis | Convolvulaceae
|
| COPU11 | Convolvulus purpureus L. | Ipomoea purpurea | Convolvulaceae
|
| COPU20 | Convolvulus purshianus Wherry | Calystegia spithamaea ssp. purshiana | Convolvulaceae
|
| CORE5 | Convolvulus repens L. | Calystegia sepium ssp. angulata | Convolvulaceae
|
| COSC10 | Convolvulus scammonia L. | scammony | Convolvulaceae
|
| COSEA | Convolvulus sepium L. var. americanus Sims | Calystegia sepium ssp. americana | Convolvulaceae
|
| COSEC | Convolvulus sepium L. var. communis R. Tryon | Calystegia sepium ssp. sepium | Convolvulaceae
|
| COSED | Convolvulus sepium L. var. dumetorum Pospichal | Calystegia sepium ssp. binghamiae | Convolvulaceae
|
| COSEF | Convolvulus sepium L. var. fraterniflorus Mackenzie & Bush | Calystegia silvatica ssp. fraterniflora | Convolvulaceae
|