Abstract A description is provided for Puccinia oahuensis . Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Digitaria spp., including D. eriantha, D. pentzii (woolly finger grass), D. smutsii and D. decumbens (pangola grass); D. sanguinalis (crab grass) is also attacked DISEASE: Rust of Digitaria spp., including several pasture or fodder grasses of agricultural or horticultural significance. GEOGRAPHICAL DISTRIBUTION: Widespread in warmer regions including USA (south-eastern states and Texas); Central and South America (Honduras, Panama, Paraguay, Argentina, Brazil and French Guiana); West Indies (Cuba, Dominica, Guadeloupe, Jamaica, Martinique, Puerto Rico and Trinidad); Middle East (Israel); Africa (Ethiopia, Ghana, Guinea, Ivory Coast, Kenya, Malawi, Mozambique, Rhodesia, S. Africa, Sierra Leone, Sudan, Tanzania, Uganda, Zambia and Mauritius); Asia (China, India, Japan, Philippines and Taiwan); Australasia and Oceania (Australia, New Guinea and Hawaii) (From literature cited and specimens in Herb. IMI).