U.S. Department of Agriculture, Agricultural Research Service Systematic Mycology and Microbiology Laboratory - Invasive Fungi Fact Sheets Common Asian Rubus Rust-Hamaspora acutissima This is one of numerous rust fungi that attack species of Rubus and are widespread in Asia. They do not appear to be very damaging. The elongated teliospores of species of Hamaspora are distinctive. Hamaspora acutissima P. Syd. & Syd. 1912 Spermogonia and aecia unknown. Uredinia hypophyllous (on lower surface of leaves), sparse, minute, orange-yellow; urediniospores globose, subglobose or ellipsoid, 18-28 × 13-20 µm, walls yellow, echinulate, 1-2 µm thick, germ pores 5-6, scattered. Telia amphigenous (on upper and lower side of leaves), mainly hypophyllous, filiform, up to 8 mm, white or pale yellow; teliospores cylindrical or obclavate to acicular, 3- to 6-celled (mostly 4- to 5-celled) constricted at septum, 120-240 µm ×, 16-25 µm, apical cells long, 20-35 µm long, acuminate at apices, walls yellow, smooth, germ pores 1 per cell; pedicels long, persistent, up to 800 µm long, 10-15 µm wide. See Hiratsuka et al. (1992) and Monoson (1969) for a more detailed description. Host Range: Uredinial and telial state: Rubus alceifolius Poir. Rubus calycinoides Hayata Rubus elmeri Focke Rubus formosensis Kuntze Rubus fraxinifolius Poir. Rubus glomeratus Blume Rubus laciniatostipulatus Hayata & Koidz. Rubus moluccanus L. Rubus nantoensis Hayata Rubus nesiotes Focke & Focke Rubus niveus Thunb. Rubus parkeri Hance Rubus pectinellus Maxim. Rubus pyrifolius Sm. Rubus rolfei S. Vidal Rubus rosaefolius Sm. Rubus setchuenensis Bureau & Franch. Rubus sp. Rubus swinhoei Hance Rubus tagallus Cham. & Schlecht. Geographic distribution: Australia, Far East Asia (China, Indonesia, Japan, New Caledonia, Papua-New Guinea, Philippines, Taiwan) Notes: This is one of the most common species of Hamaspora on Rubus and is quite distinctive in having very long, threadlike teliospores. References: Boedijn, K.B. 1959. The Uredinales of Indonesia. Nova Hedwigia 1: 463-496. Monoson, H.L. 1969. The species of Hamaspora. Mycopathol. Mycol. Appl. 37: 263-272. Mouchacca, J., and Horak, E. 1998. Annotated checklist of New Caledonian Basidiomycota. II. Rusts and Smuts. Mycotaxon 69: 13-30. Shivas R. G., and Alcorn, J.L. 1996. A checklist of plant pathogenic and other microfungi in the rainforests of the wet tropics of northern Queensland. Australas. Mycol. 25: 158-173. Teodoro, N.G. 1937. An Enumeration of Philippine Fungi. Techn. Bull. Dept. Agric. Comm. Manila 4: 1-585. Watson, A.J. 1971. Foreign bacterial and fungus diseases of food, forage, and fiber crops. U.S.D.A. Agricultural Research Service : 111. Suggested citation: Yun, H.Y..Systematic Mycology and Microbiology Laboratory, ARS, USDA. Invasive Fungi. Common Asian Rubus Rust-Hamaspora acutissima. Retrieved September 29, 2021, from /sbmlweb/fungi/index.cfm . Use this link to revisit SMML website Telia of H. acutissima upper surface of Rubus spp. Telia of H. acutissima lower surface of leaves of Rubus leaves spp. Telia of H. acutissima upper surface of leaves of Rubus 4. Telia of H. acutissima lower surface of Rubus spp. spp. (× 6) Leaves (× 10) Teliospore of H. acutissima of Rubus spp. by LM (× 400, Teliospore of H. acutissima of Rubus spp. by LM (× 200, Scale bar: 50 ¼m) Scale bar: 100 ¼m) .