A stage lighting fixture having: a casing having a closed first end and an open second end; 5 a light source housed inside the casing, close to the first end, and which emits a light beam along an optical axis; an optical assembly positioned to intercept the light beam, and having a focal point located between the light source and the optical assembly; and a reflector coupled to the light source; the reflector and the light source being designed and coupled to concentrate the light beam substantially at a work point substantially coincident with the focal point of the optical assembly; and the light source being defined by a short-arc lamp to project a light bar.