Trevisan, 1889.

Description – A Bacteria!! Not a fungus!!

Colonies are slow growing, aerobic, gram-positive, acid-fast to partially acid-fast, glabrous, heaped and folded, and white, pink, red, orange, or tan in color. Filaments are branched, fragmenting into rod and coccoid forms. Aerial filaments usually present.

Salient Characteristics

Medically important species of Nocardia are lysozyme resistant and do not produce acid from cellobiose.

Laboratory Precautions

Handle with care, but special precautions are not necessary.

Key reference

Goodfellow and Minnikin, 1977
Mishra, Gordon, and Barnett, 1980


  • Nocardia asteroides
  • Nocardia brasiliensis
  • Nocardia otitidiscaviarum


  • mycetoma
  • nocardiosis

Sensitivity Testing






Natural Habitat