| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| COCO15 | Coronaria coriacea (Moench) Schischkin & Gorschk. | Lychnis coronaria | Caryophyllaceae
|
| COFL10 | Coronaria flos-cuculi (L.) A. Braun | Lychnis flos-cuculi | Caryophyllaceae
|
| COCR10 | Coronilla cretica L. | Cretan crownvetch | Fabaceae
|
| COEM3 | Coronilla emerus L. | scorpion senna | Fabaceae
|
| COGL17 | Coronilla globosa Lam. | white crownvetch | Fabaceae
|
| COSC5 | Coronilla scorpioides (L.) W.D.J. Koch | yellow crownvetch | Fabaceae
|
| COSE10 | Coronilla securidaca L. | goat pea | Fabaceae
|
| COVA4 | Coronilla valentina L. | Mediterranean crownvetch | Fabaceae
|
| COVA2 | Coronilla varia L. | purple crownvetch | Fabaceae
|
| CORON | Coronilla L. | crownvetch | Fabaceae
|
| CODI6 | Coronopus didymus (L.) Sm. | lesser swinecress | Brassicaceae
|
| COPR3 | Coronopus procumbens Gilib. | Coronopus squamatus | Brassicaceae
|
| COSQ | Coronopus squamatus (Forsk.) Aschers. | greater swinecress | Brassicaceae
|
| CORON3 | Coronopus Zinn | swinecress | Brassicaceae
|
| COOL2 | Corozo oleifera (Kunth) L. H. Bailey | Elaeis oleifera | Arecaceae
|
| COBA13 | Correa backhousiana Hook. | Backhous fuchsia | Rutaceae
|
| CORRE | Correa Andrews, nom. cons. | Australian fuschia | Rutaceae
|
| COLI6 | Corrigiola litoralis L. | strapwort | Caryophyllaceae
|
| CORRI | Corrigiola L. | corrigiola | Caryophyllaceae
|
| CORRY | Corryocactus Britton & Rose | corryocactus | Cactaceae
|
| COCO39 | Corsinia coriandrina (Spreng.) Lindb. | | Corsiniaceae
|
| CORSI | Corsinia Raddi | | Corsiniaceae
|
| COAT2 | Cortaderia atacamensis (Phil.) Pilger | Cortaderia jubata | Poaceae
|
| CODI11 | Cortaderia dioica (Spreng.) Speg. | Cortaderia selloana | Poaceae
|
| COJU2 | Cortaderia jubata (Lem.) Stapf | purple pampas grass | Poaceae
|
| COSE4 | Cortaderia selloana (J.A. & J.H. Schultes) Aschers. & Graebn. | Uruguayan pampas grass | Poaceae
|
| COTO6 | Cortaderia toetoe Zotov | toetoe | Poaceae
|
| CORTA | Cortaderia Stapf | pampas grass | Poaceae
|
| COFU4 | Corticifraga fuckelii (Rehm) D. Hawksw. & R. Sant. | | Uncertain Lichen Family
|
| CORTI | Corticifraga D. Hawksw. & R. Sant. | corticifraga | Uncertain Lichen Family
|
| COAQ | Corydalis aquae-gelidae M.E. Peck & Wilson | Corydalis caseana ssp. aquae-gelidae | Fumariaceae
|
| COAUO2 | Corydalis aurea Willd. ssp. occidentalis (Engelm. ex Gray) G.B. Ownbey | Corydalis curvisiliqua ssp. occidentalis | Fumariaceae
|
| COAUA2 | Corydalis aurea Willd. var. australis Chapman | Corydalis micrantha ssp. australis | Fumariaceae
|
| COAUM | Corydalis aurea Willd. var. micrantha Engelm. ex Gray | Corydalis micrantha ssp. micrantha | Fumariaceae
|
| COAUO | Corydalis aurea Willd. var. occidentalis Engelm. ex Gray | Corydalis curvisiliqua ssp. occidentalis | Fumariaceae
|
| COAU2 | Corydalis aurea Willd. | scrambled eggs | Fumariaceae
|
| COBI8 | Corydalis bidwelliae S. Wats. | Corydalis caseana ssp. caseana | Fumariaceae
|
| COBR4 | Corydalis brandegeei S. Wats. | Corydalis caseana ssp. brandegeei | Fumariaceae
|
| COBU2 | Corydalis bulbosa (L.) DC. | Corydalis solida | Fumariaceae
|
| COCA25 | Corydalis campestris (Britt.) Buchh. & Palmer | Corydalis micrantha ssp. australis | Fumariaceae
|
| COCAA | Corydalis caseana Gray ssp. aquae-gelidae (M.E. Peck & Wilson) Zetterlund & Lid�n | coldwater fumewort | Fumariaceae
|
| COCAB | Corydalis caseana Gray ssp. brachycarpa (Rydb.) G.B. Ownbey | Sierra fumewort | Fumariaceae
|
| COCAB2 | Corydalis caseana Gray ssp. brandegeei (S. Wats.) G.B. Ownbey | Brandegee's fumewort | Fumariaceae
|
| COCAC7 | Corydalis caseana Gray ssp. caseana | Sierra fumewort | Fumariaceae
|
| COCAC | Corydalis caseana Gray ssp. cusickii (S. Wats.) G.B. Ownbey | Cusick's fumewort | Fumariaceae
|
| COCAH2 | Corydalis caseana Gray ssp. hastata (Rydb.) G.B. Ownbey | Sierra fumewort | Fumariaceae
|
| COCAC2 | Corydalis caseana Gray var. cusickii (S. Wats.) C.L. Hitchc. | Corydalis caseana ssp. cusickii | Fumariaceae
|
| COCAH | Corydalis caseana Gray var. hastata (Rydb.) C.L. Hitchc. | Corydalis caseana ssp. hastata | Fumariaceae
|
| COCA15 | Corydalis caseana Gray | Sierra fumewort | Fumariaceae
|
| COCR2 | Corydalis crystallina Engelm. | mealy fumewort | Fumariaceae
|
| COCUC | Corydalis curvisiliqua Engelm. ssp. curvisiliqua | curvepod fumewort | Fumariaceae
|
| COCUG2 | Corydalis curvisiliqua Engelm. ssp. grandibracteata (Fedde) G.B. Ownbey | curvepod fumewort | Fumariaceae
|
| COCUO | Corydalis curvisiliqua Engelm. ssp. occidentalis (Engelm. ex Gray) W.A. Weber | curvepod fumewort | Fumariaceae
|
| COCUG | Corydalis curvisiliqua Engelm. var. grandibracteata Fedde | Corydalis curvisiliqua ssp. grandibracteata | Fumariaceae
|
| COCU2 | Corydalis curvisiliqua Engelm. | curvepod fumewort | Fumariaceae
|
| COCU3 | Corydalis cusickii S. Wats. | Corydalis caseana ssp. cusickii | Fumariaceae
|
| COFL3 | Corydalis flavula (Raf.) DC. | yellow fumewort | Fumariaceae
|
| COHA3 | Corydalis halei (Small) Fern. & Schub. | Corydalis micrantha ssp. australis | Fumariaceae
|
| COLU | Corydalis lutea (L.) DC. | Pseudofumaria lutea | Fumariaceae
|
| COMIA2 | Corydalis micrantha (Engelm. ex Gray) Gray ssp. australis (Chapman) G.B. Ownbey | smallflower fumewort | Fumariaceae
|
| COMIM2 | Corydalis micrantha (Engelm. ex Gray) Gray ssp. micrantha | smallflower fumewort | Fumariaceae
|
| COMIT2 | Corydalis micrantha (Engelm. ex Gray) Gray ssp. texensis G.B. Ownbey | Texan fumewort | Fumariaceae
|
| COMIA | Corydalis micrantha (Engelm. ex Gray) Gray var. australis (Chapman) Shinners | Corydalis micrantha ssp. australis | Fumariaceae
|
| COMIT | Corydalis micrantha (Engelm. ex Gray) Gray var. texensis (G.B. Ownbey) Shinners | Corydalis micrantha ssp. texensis | Fumariaceae
|
| COMI2 | Corydalis micrantha (Engelm. ex Gray) Gray | smallflower fumewort | Fumariaceae
|
| COMO6 | Corydalis montana Engelm. | Corydalis curvisiliqua ssp. occidentalis | Fumariaceae
|
| COPAA | Corydalis pauciflora (Steph.) Pers. var. albiflora Porsild | Corydalis pauciflora | Fumariaceae
|
| COPAC | Corydalis pauciflora (Steph.) Pers. var. chamissonis Fedde | Corydalis pauciflora | Fumariaceae
|
| COPA11 | Corydalis pauciflora (Steph.) Pers. | fewflower fumewort | Fumariaceae
|
| COSC4 | Corydalis scouleri Hook. | Scouler's fumewort | Fumariaceae
|
| COSE5 | Corydalis sempervirens (L.) Pers. | rock harlequin | Fumariaceae
|
| COSO6 | Corydalis solida (L.) Clairv. | spring fumewort | Fumariaceae
|
| COWA5 | Corydalis washingtoniana Fedde | Corydalis aurea | Fumariaceae
|
| CORYD | Corydalis DC. | fumewort | Fumariaceae
|
| COSI12 | Corylopsis sinensis Hemsl. | winter hazel | Hamamelidaceae
|
| CORYL2 | Corylopsis Sieb. & Zucc. | winter hazel | Hamamelidaceae
|
| COAMI | Corylus americana Walt. var. indehiscens Palmer & Steyermark | Corylus americana | Betulaceae
|
| COAM3 | Corylus americana Walt. | American hazelnut | Betulaceae
|
| COAV80 | Corylus avellana L. | common filbert | Betulaceae
|
| COCA23 | Corylus californica (A. DC.) Rose | Corylus cornuta var. californica | Betulaceae
|
| COCH7 | Corylus chinensis Franchet | Corylus colurna var. chinensis | Betulaceae
|
| COCOC6 | Corylus colurna L. var. chinensis (Franchet) Burkill | Chinese hazelnut | Betulaceae
|
| COCOC5 | Corylus colurna L. var. colurna | Turkish hazelnut | Betulaceae
|
| COCO30 | Corylus colurna L. | Turkish hazelnut | Betulaceae
|
| COCOC | Corylus cornuta Marsh. var. californica (A. DC.) Sharp | California hazelnut | Betulaceae
|
| COCOC2 | Corylus cornuta Marsh. var. cornuta | beaked hazelnut | Betulaceae
|
| COCO6 | Corylus cornuta Marsh. | beaked hazelnut | Betulaceae
|
| COFEF | Corylus ferox Wallich var. ferox | Himalayan hazelnut | Betulaceae
|
| COFET | Corylus ferox Wallich var. thibetica (Batalin) Franchet | Tibetan hazelnut | Betulaceae
|
| COFE5 | Corylus ferox Wallich | Himalayan hazelnut | Betulaceae
|
| COHE12 | Corylus heterophylla Fisch. & Trautv. | Siberian hazelnut | Betulaceae
|
| COMA18 | Corylus maxima Miller | giant filbert | Betulaceae
|
| CORO5 | Corylus rostrata Ait. | Corylus cornuta var. cornuta | Betulaceae
|
| COTH2 | Corylus thibetica Batalin | Corylus ferox var. thibetica | Betulaceae
|
| CORYL | Corylus L. | hazelnut | Betulaceae
|
| COTE20 | Corymbia terminalis (F. Muell.) K. D. Hill & L. A. S. Johnson | | Myrtaceae
|
| CORYM3 | Corymbia K.D. Hill & L.A.S. Johnson | corymbia | Myrtaceae
|
| COFO7 | Corymborkis forcipigera (Reichenb. f. & Warszewicz) L.O. Williams | | Orchidaceae
|
| CORYM2 | Corymborkis Thouars | crow orchid | Orchidaceae
|
| COPA15 | Corynella paucifolia DC. | Poitea paucifolia | Fabaceae
|
| COCA16 | Corynephorus canescens (L.) Beauv. | gray clubawn grass | Poaceae
|