| chiromantes haematocheir | Yes | species | eukaryota | invertebrates | species | 151164 | click here |
| chloraea gavilu | Yes | species | | | species | 993479 | click here |
| chlorella vulgaris | Yes | species | eukaryota | plants | species | 3077 | click here |
| chloris barbata | Yes | species | eukaryota | plants | species | 167333 | click here |
| chlorophyllum rhacodes | Yes | species | eukaryota | plants | species | 34436 | click here |
| chlorophyta | Yes | | | plants | phylum | 3041 | click here |
| chlorophytum | Yes | | | plants | genus | 16046 | click here |
| chlorophytum comosum | Yes | species | eukaryota | plants | species | 34182 | click here |
| chondrosia reniformis | Yes | species | eukaryota | invertebrates | species | 68574 | click here |
| chondrus crispus | Yes | species | eukaryota | plants | species | 2769 | click here |
| chromolaena laevigata | Yes | species | | | species | 1745036 | click here |
| chromolaena odorata | Yes | species | eukaryota | plants | species | 103745 | click here |
| chroogomphus rutilus | Yes | species | eukaryota | plants | species | 85976 | click here |
| chrysanthemum lavandulifolium | Yes | species | eukaryota | plants | species | 146996 | click here |
| chrysomelidae | Yes | | | invertebrates | family | 27439 | click here |
| cicer arietinum | Yes | species | eukaryota | plants | species | 3827 | click here |
| cichorium intybus | Yes | species | eukaryota | plants | species | 13427 | click here |
| ciconia ciconia | Yes | species | eukaryota | vertebrates | species | 8928 | click here |
| cinchona calisaya | Yes | species | eukaryota | plants | species | 153742 | click here |
| cinnamomum aromaticum | Yes | species | eukaryota | plants | species | 119260 | click here |
| cinnamomum longipaniculatum | Yes | species | eukaryota | plants | species | 470718 | click here |
| cinnamomum verum | Yes | species | eukaryota | plants | species | 128608 | click here |
| ciona intestinalis | Yes | species | eukaryota | invertebrates | species | 7719 | click here |
| ciona robusta | Yes | species | | | species | 1774208 | click here |
| citheronia lobesis | Yes | species | eukaryota | invertebrates | species | 316025 | click here |
| citrullus colocynthis | Yes | species | eukaryota | plants | species | 252529 | click here |
| citrullus lanatus | Yes | species | eukaryota | plants | species | 3654 | click here |
| citrullus lanatus subsp. vulgaris | Yes | subspecies | eukaryota | plants | subspecies | 260674 | click here |
| citrus | Yes | | | plants | genus | 2706 | click here |
| citrus aurantium | Yes | species | eukaryota | plants | species | 43166 | click here |
| citrus latifolia | Yes | species | eukaryota | plants | species | 200541 | click here |
| citrus limon | Yes | species | eukaryota | plants | species | 2708 | click here |
| citrus limonia | Yes | species | eukaryota | plants | species | 171249 | click here |
| citrus maxima | Yes | species | eukaryota | plants | species | 37334 | click here |
| citrus medica | Yes | species | eukaryota | plants | species | 171251 | click here |
| citrus reticulata | Yes | species | eukaryota | plants | species | 85571 | click here |
| citrus sinensis | Yes | species | eukaryota | plants | species | 2711 | click here |
| citrus unshiu | Yes | species | eukaryota | plants | species | 55188 | click here |
| citrus x paradisi | Yes | subspecies | eukaryota | plants | species | 37656 | click here |
| cladophora | Yes | | | plants | genus | 34125 | click here |
| clarias gariepinus | Yes | species | eukaryota | vertebrates | species | 13013 | click here |
| clavelina lepadiformis | Yes | species | eukaryota | invertebrates | species | 159417 | click here |
| cleisostoma williamsonii | Yes | species | | | species | 1497770 | click here |
| clinacanthus nutans | Yes | species | eukaryota | plants | species | 714457 | click here |
| cnidoscolus aconitifolius | Yes | species | eukaryota | plants | species | 398630 | click here |
| coccinella septempunctata | Yes | species | eukaryota | invertebrates | species | 41139 | click here |
| coccinellidae | Yes | | | invertebrates | family | 7080 | click here |
| cocos nucifera | Yes | species | eukaryota | plants | species | 13894 | click here |
| codium | Yes | | | plants | genus | 3132 | click here |
| codium fragile | Yes | species | eukaryota | plants | species | 3133 | click here |
| codium tomentosum | Yes | species | | | species | 713099 | click here |
| codonopsis lanceolata | Yes | species | eukaryota | plants | species | 103999 | click here |
| coelarthrum | Yes | | | plants | genus | 81595 | click here |
| coelogyne flaccida | Yes | species | eukaryota | plants | species | 71595 | click here |
| coffea | Yes | | | plants | genus | 13442 | click here |
| coffea arabica | Yes | species | eukaryota | plants | species | 13443 | click here |
| coleostephus myconis | Yes | species | eukaryota | plants | species | 99042 | click here |
| colinus virginianus | Yes | species | eukaryota | vertebrates | species | 9014 | click here |
| colobanthus quitensis | Yes | species | eukaryota | plants | species | 552857 | click here |
| colocasia esculenta | Yes | species | eukaryota | plants | species | 4460 | click here |
| colophospermum mopane | Yes | species | eukaryota | plants | species | 162715 | click here |
| colopterus truncatus | Yes | species | | | species | 1847791 | click here |
| colpomenia | Yes | | | plants | genus | 27964 | click here |
| colpomenia sinuosa | Yes | species | eukaryota | plants | species | 87236 | click here |
| columnea minutiflora | Yes | species | eukaryota | plants | species | 356125 | click here |
| comarum palustre | Yes | species | eukaryota | plants | species | 57932 | click here |
| comaster schlegelii | Yes | species | | | species | 1529421 | click here |
| convolvulus arvensis | Yes | species | eukaryota | plants | species | 4123 | click here |
| convolvulus fruticosus | Yes | species | | | species | 1428909 | click here |
| copaifera langsdorffii | Yes | species | eukaryota | plants | species | 280048 | click here |
| coptotermes formosanus | Yes | species | eukaryota | invertebrates | species | 36987 | click here |
| corallina officinalis | Yes | species | eukaryota | plants | species | 35170 | click here |
| corethrodendron scoparium | Yes | species | | | species | 1402424 | click here |
| cornulaca | Yes | | | plants | genus | 454474 | click here |
| cornulaca monacantha | Yes | species | eukaryota | plants | species | 454476 | click here |
| cornus | Yes | | | plants | genus | 4281 | click here |
| cornus alba | Yes | species | eukaryota | plants | species | 367337 | click here |
| corticium candelabrum | Yes | species | eukaryota | invertebrates | species | 121492 | click here |
| corydalis yanhusuo | Yes | species | eukaryota | plants | species | 458692 | click here |
| corylus avellana | Yes | species | eukaryota | plants | species | 13451 | click here |
| cosmos caudatus | Yes | species | | | species | 1125397 | click here |
| costus pictus | Yes | species | eukaryota | plants | species | 168183 | click here |
| cotoneaster | Yes | | | plants | genus | 36607 | click here |
| coturnix coturnix | Yes | species | eukaryota | vertebrates | species | 9091 | click here |
| coturnix japonica | Yes | species | eukaryota | vertebrates | species | 93934 | click here |
| crassostrea gigas | Yes | species | eukaryota | invertebrates | species | 29159 | click here |
| crassula | Yes | | | plants | genus | 3782 | click here |
| crataegus crus-galli | Yes | no rank | eukaryota | plants | species | 216036 | click here |
| crataegus monogyna | Yes | species | eukaryota | plants | species | 140997 | click here |
| crescentia cujete | Yes | species | | | species | 1125401 | click here |
| crinoidea | Yes | | | invertebrates | class | 35069 | click here |
| crithmum maritimum | Yes | species | eukaryota | plants | species | 40916 | click here |
| crocus sativus | Yes | species | eukaryota | plants | species | 82528 | click here |
| crustacea | Yes | | | invertebrates | subphylum | 6657 | click here |
| cryptotympana facialis | Yes | species | eukaryota | invertebrates | species | 911377 | click here |
| cucumis melo | Yes | species | eukaryota | plants | species | 3656 | click here |
| cucumis sativus | Yes | species | eukaryota | plants | species | 3659 | click here |
| cucurbita | Yes | | | plants | genus | 3660 | click here |
| cucurbita pepo | Yes | species | eukaryota | plants | species | 3663 | click here |
| culex | Yes | | | invertebrates | genus | 7174 | click here |