C. nigricans

C. nigricans may refer to:
 * Caecilia nigricans, an amphibian species found in Colombia, Ecuador and Panama
 * Calyptranthes nigricans, DC., a plant species in the genus Calyptranthes
 * Camponotus nigricans, Roger, 1863, an ant species in the genus Camponotus
 * Carex nigricans, a species of sedge
 * Celaenorrhinus nigricans, the small banded flat, a butterfly species found in South and Southeast Asia
 * Cercomacra nigricans, the jet antbird, a bird species found in Brazil, Colombia, Ecuador, Panama and Venezuela
 * Chalcosyrphus nigricans, Shiraki, 1968, an hoverfly species in the genus Chalcosyrphus
 * Chinemys nigricans, the red-necked pond turtle, a turtle species endemic to China
 * Clanculus nigricans, a sea snail species in the genus Clanculus
 * Clarias nigricans, a catfish species only known from the Mahakam River in eastern Borneo
 * Claviceps nigricans a species of Ergot fungi
 * Corunastylis nigricans, (R.Br.) D.L.Jones & M.A.Clem., the Mallee midge-orchid, a plant species in the genus Corunastylis
 * Creugas nigricans,C. L. Koch, 1841, a spider species in the genus Creugas and the family Corinnidae found in Mexico and Colombia
 * Crocidura nigricans, the blackish white-toothed shrew, a mammal species endemic to Angola
 * Cyathea nigricans, a tree fern species in the genus Cyathea
 * Cyerce nigricans, a sacoglossan sea slug species