Sporisorium mysorense (Pavgi & Thirum.) Vánky, Mycotaxon

Denchev, Teodor T., Sun, Hang, Denchev, Cvetomir M. & Boufford, David E., 2016, A new smut fungus on a new grass: Sporisorium capillipedii-alpini (Ustilaginales) sp. nov. infecting Capillipedium alpinum (Poaceae) sp. nov., from Sichuan, China, Phytotaxa 252 (3), pp. 217-227 : 224-226

Sporisorium mysorense (Pavgi & Thirum.) Vánky, Mycotaxon 54: 230, 1995. ( Figs 20–25 )

Basionym: Sphacelotheca mysorensis Pavgi & Thirum. , in Thirumalachar & Pavgi, Sydowia 6: 394, 1952.

Type: —On Capillipedium huegelii ( Poaceae ). INDIA. Mysore, Shimoga District: at Bedur, May 1951, leg. B. T. Lingappa (holotype, HCIO 20 130; isotypes BPI 190 144, IMI 52 805, H. U. V. 16 039!).

Sori in all spikelets of the inflorescence, single sterile spikelets may not be infected, 0.7–1.8 × 0.4–0.8 mm, ovoid,

partly concealed by the glumes; initially covered by a thick yellow-brown to dark brown peridium that soon ruptures irregularly exposing a single, stout, tapering, unbranched columella as long as the sorus. Columella with shallow longitudinal furrows, surrounded by a semi agglutinated, blackish brown mass of spores and sterile cells. Sterile cells in irregular groups, single sterile cells uncommon, collapsed, (6.5–)7.5–13.5(–15) μm long, subhyaline to light yellowbrown; wall 0.5–0.7 μm thick, smooth. Spores subpolygonate, slightly irregular, subglobose or broadly ellipsoidal,

(9–)10–12.5(–13.5) × (9–)9.5–11(–12) (11.3 ± 0.7 × 10.1 ± 0.6) μm (n/ 1 = 100), medium reddish brown; wall unevenly thickened, 0.7–1.0 μm thick, with a few thinner areas in which the wall is collapsed and often lighter, smooth, spore profile not affected. In SEM densely punctate, projections up to 0.1 μm high, often fused.

Specimen examined: — Isotype ( H. U. V. 16 039).

Known host and distribution: —On Poaceae : Capillipedium huegelii (Hack.) A. Camus. Asia ( India).

The species of Sporisorium that destroy all spikelets of the inflorescence of an infected plant in the genera Capillipedium, Botriochloa , and Dichanthium (but not the whole inflorescence), may be distinguished using the following key:

Figures

FIGURES 20–25. Sporisorium mysorense (Pavgi & Thirum.) Vánky on Capillipedium huegelii (isotype, H.U.V. 16 039). 20. Habit. 21–23. Spores in LM. 21, 22. In median view. 23. In surface view. 24, 25. Spores in SEM. Scale bars: 20 = 0.2 cm, 21–24 = 10 μm, 25 = 2 μm. FIGURE 26. Holotype locality of Capillipedium alpinum (blue circle) and localities of Sporisorium capillipedii-alpini on Capillipedium alpinum (red circles).