A Pseudomonas species is reported as a new pathogen of the leaves and spathe of anthurium. This vascular disease may be characterized by black necrotic spots surrounded by greasy margins and a bright chlorotic halo on leaves and a violet halo on the spathe. Symptoms observed on naturally infected material, as well as in pathogenicity tests, showed both local and systemic infections. Morphological, cytological, physiological, biochemical and serological relationships of the pathogen are presented. There is evidence that this bacterium may be a new species. The species Pseudomonas aracearum is proposed.