A. nigra may refer to:Actia nigra, a tachinid fly species Aculeola nigra, the hooktooth dogfish, a small, little known dogfish, the only member of the genus Aculeola Alpinia nigra, an herb in the ginger family Arkoola nigra, a fungus plant pathogen species Astrapia nigra, the Arfak Astrapia, a large black bird of paradise species