| Abbrev | Name | Spec | Type | Locality |
|---|---|---|---|---|
| COU | COUTICHES[144][900][1281]; | TR.AE | W | FRA |
| COURT | COURTOT | TR.AE | W | FRA:INRA |
| COW | COWBIRD[114][144][900][1281]; | TR.AE | S | MEX |
| CP,2 | CAPPELLI | TR.DR | S | ITA |
| CPA,1 | COTIPORA[145][900][1281]; | TR.AE | S | BRA |
| CPA,2 | COCHAPAMPA | TR.DR | ||
| CPEN | COPIFEN[145][900][1281]; | TR.AE | W | CHL |
| CPI | CAPEITI[145][900][1281]; | TR.DR | S | ITA |
| CPP | CAPELLI[145][219][1281]; | TR.DR | S | ITA |
| CPT | CAPEST[900][1281]; | TR.AE | W | FRA |
| CPZ | CASTEL-PORZIANO[1281]; | TR.DR | ITA | |
| CQ | CACIQUE[145][900][1281]; | TR.AE | S | BRA |
| CQI | CHASQUI-INIA[145][144][1281]; | TR.AE | S | CHL |
| CQT | CINQUENTENARIO[145][900][1281]; | TR.AE | S | BRA |
| CR,2 | CRANE[115]; | TR.DR | S | MEX |
| CRBK | CRANBROOK[144][1281]; | TR.AE | AUS | |
| CRIS | CRISTATUS[115][1281]; | TR.DR | S | MEX |
| CRMR | CORAZON-DE-MARIA[145][900][1281]; | TR.AE | S | CHL |
| CRN | CARDINAL[740][900] | TR.AE | S | DEU |
| CRN-U | CARDINAL[740]; | TR.AE | W | USA |