Urocystis occulta (Wallr.) A. A. Fisch. Waldh. 1867

Foodplant / parasite
sorus of Urocystis occulta parasitises live inflorescence of Secale cereale
Remarks: season: 6

Urocystis occulta (Walir.) Rab.; Klotzsch, Herb. Viv. Myc
ed. 2. 393. 1856.
Erysibe occulta Wallr. Fl. Crypt. Germ. 2 : 212. 1833.
Sori in leaves (especially on inner side of sheaths), culm and inflorescence, forming linear striae usually of great length and often merged into a continuous stratum of dusty reddish-black spore-balls ; spore-balls oblong to subspherical, 16-32 /^ in length ; sterile cells often incompletely covering the spores, hyaline or yellowish-tinted, subspherical to oblong usually with distended and uniformly thickened walls; spores reddish-brown, oblong'to subspherical, often with sides flattened, smooth, 1 or 2, rarely 3 or 4 in a ball, 11-18 // in length.
^^ I'^cauf create , Connecticut, Massachusetts, Minnesota, New Jersey, New York, Ohio,
Rhode Island ; Nova Scotia.
STs™b.'^ionT N^ricTtia^'Jo^SL'n^sX' and New Jersey ; also in South An^erica, Europe, and Australia. ^ggp . .^ 2, f. 9-11; Bull. Conn. Geol. Nat.
Econ. Fungi 98^; Kellerm. Ohio Fungi J^.

Urocystis occulta is a smut fungus which attacks the leaves and stalks of rye (Secale cereale). It is found in Australia, Europe, and North America. The fungus was first described by German botanist Karl Friedrich Wilhelm Wallroth under the name Erysiphe occulta in 1833.