Jamesdicksonia anadelphiae-trichaetae T. Denchev & Denchev, 2016

Denchev, Teodor T. & Denchev, Cvetomir M., 2016, Jamesdicksonia anadelphiae-trichaetae (Georgefischeriales) and Sporisorium anadelphiae-trichaetae (Ustilaginales), new species on Anadelphia trichaeta (Poaceae) from Guinea, Phytotaxa 252 (3), pp. 205-216 : 208-210

Jamesdicksonia anadelphiae-trichaetae T. Denchev & Denchev , sp. nov. ( Figs 12–27 )

Index Fungorum number: IF551657

Type: —On Anadelphia trichaeta (Reznik) Clayton ( Poaceae ). GUINEA. Labé Region: Labé, Bowal Guessé, 26 October 1956, leg. J. G. Adam 30 832 ( B 70 0015713, holotype).

Diagnosis: — Jamesdicksonia anadelphiae-trichaetae differs from J. anadelphiae by having larger spores with thicker spore walls. The sori of J. anadelphiae-trichaetae are erumpent while that of J. anadelphiae are non-erumpent.

Etymology: —Epithet derived from the host plant, Anadelphia trichaeta .

Sori in leaves and spatheoles, forming flat or slightly swollen, lead-colored streaks, limited by veins, 0.5–5.0 × 0.1–0.8 mm; usually developing on the upper side of the leaves and spatheoles, later amphigenous, erumpent; initially covered by the epidermis that later ruptures longitudinally—first on the upper, later on the lower side of the leaves and spatheoles. Spore mass blackish brown, agglutinated to semi agglutinated. Spores packed in elongated or irregular groups, sometimes single, variable in shape and size, subpolygonal, slightly to moderately irregular, subglobose, broadly ellipsoidal, ovoid, sometimes ellipsoidal, irregularly elongated or cuneate, (11.5–)13–23.5(–26.5) × (9.5–)10.5–19(–20) (17.6 ± 2.9 × 14.0 ± 2.0) μm (n = 200), medium to dark reddish brown, sometimes with an appendage ( Fig. 22 ); wall two-layered, (2.0–)2.5–7.0(–9.0) μm thick; inner layer more or less evenly thickened, 0.7–1.7(–2.0) μm thick, slightly lighter in color than the outer layer; the latter (as seen by LM) laminated, with up to 7(–10) layers ( Figs 18, 23, 24 ), variable in visibility in different spores. In LM the surface of the mature spores looks more or less cracked ( Figs 19, 20 ), in SEM rugose.

Known host and distribution: —On Poaceae : Anadelphia trichaeta , Africa ( Guinea) (Fig. 11). Known only from the type collection.

Comments: — Jamesdicksonia anadelphiae-trichaetae differs from J. anadelphiae by having larger spores, (11.5–)13–23.5(–26.5) (17.6 ± 2.9) μm long versus (9–)9.5–15.5(–18.5) (12.9 ± 1.7) μm long for J. anadelphiae , with thicker spore wall, (2.0–)2.5–7.0(–9.0) μm thick versus 1.2–3.0(–3.8) μm thick for J. anadelphiae . The sori of J. anadelphiae-trichaetae are erumpent while that of J. anadelphiae are non-erumpent. The following additional differences were observed: (i) in LM, the outer layer of the spore wall of J. anadelphiae-trichaetae is more distinctly laminated (with up to 7(–10) layers) while that of J. anadelphiae is only sometimes laminated, with up to 3(–4), hardly distinguishable layers; (ii) in LM, the surface of the mature spores of J. anadelphiae-trichaetae looks more or less cracked, and in SEM, it is rugose while the spore surface of J. anadelphiae is smooth in LM, and rugulose in SEM; (iii) the color of the spores of J. anadelphiae-trichaetae is middle to dark reddish brown versus middle olivaceous brown for J. anadelphiae ; (iv) the spores of the new species are somewhat more irregular in shape.

Specimen B 70 0021869 (originally labelled as infected by Sporisorium andropogonis ) consists of two smut fungi, Jamesdicksonia anadelphiae-trichaetae and Sporisorium anadelphiae-trichaetae , with some individual plants simultaneously infected by both of these smut fungi (Figs 14, 15).

Anthracocystis anadelphiae (Vienn.-Bourg.) McTaggart & R.G. Shivas, in McTaggart et al., Persoonia 29: 119, 2012. ( Figs 28–34 )

Basionym: Sorosporium anadelphiae Vienn. -Bourg., Bull. Soc. Bot. France 104: 272, 1957.

Synonym: Sporisorium anadelphiae (Vienn.-Bourg.) Vánky, Mycotaxon 85: 58, 2003.

Type: —On Anadelphia pumila Jacq. -Fél. ( Poaceae ). GUINEA. Kindia Region: Foulaya near Kindia, wet sandstone, January 1957, leg. G. Viennot-Bourgin (holotype, PC; isotype, H. U. V. 15 800!).

Sori in some spikelets ( Fig. 29 ) or groups of spikelets ( Fig. 28 ) in the inflorescence, 3–10 × 0.3–1.3 mm, fusiform, tapering at both ends, partly concealed by the glumes, initially covered by a thick brownish peridium that soon ruptures irregularly from its distal part or longitudinally on the sides, exposing a single, filiform, sometimes branched columella, surrounded by a granular blackish brown mass of spore balls. Spore balls subglobose, broadly ellipsoidal, ellipsoidal, ovoid or irregular, 55–155(–175) × 40–120(–150) μm, dark reddish brown, often opaque, composed of (tens–) hundreds, rather firmly united spores that separates under strong pressure. Sterile cells absent. Spores dimorphic ( Figs 31, 32 ), subpolyhedral, globose, subglobose, broadly ellipsoidal or ovoid, often flattened on the contact sides (especially the inner spores). Outer spores (9.5–)10.5–15(–16) × (8.5–)9.5–13(–14) (12.6 ± 1.1 × 10.9 ± 1.0) μm (n = 100), medium reddish brown; wall uneven, 0.6–2.3(–2.6) μm thick, thicker on the free surface, smooth to minutely verruculose on the contact sides, verrucose on the free surface, spore profile affected. In SEM on the free surface densely echinate to coarsely verrucose, ornaments up to 0.6 μm high, often fused in irregular groups or rows, the surface between the main ornaments verruculose. Inner spores (8–)9–12.5(–13.5) × (7.5–)8–11(–12) (10.7 ± 1.0 × 9.3 ± 0.7) μm (n = 100), light yellowish brown; wall evenly or almost evenly thickened, 0.5–0.9 μm thick, smooth.

Specimen examined: — Isotype ( H. U. V. 15 800).

Known host and distribution: —On Poaceae : Anadelphia pumila , Africa ( Guinea) (Fig. 11). Known only from the type collection.

Figures

FIGURES 12, 13. Jamesdicksonia anadelphiae-trichaetae on Anadelphia trichaeta (holotype, B 70 0015713). Habit. Scale bars = 0.5 cm. FIGURES 14, 15. Anadelphia trichaeta, simultaneously infected by Jamesdicksonia anadelphiae-trichaetae and Sporisorium anadelphiae-trichaetae (B 70 0021869). Black arrows indicate sori of Sporisorium anadelphiae-trichaetae. Scale bars = 0.5 cm.

FIGURES 16–27. Jamesdicksonia anadelphiae-trichaetae on Anadelphia trichaeta (holotype, B 70 0015713). 16–24. Spores in LM. Vascular bundle (indicated with a black arrow) with a group of spores are illustrated in Fig. 16. Note the spores in surface view in Figs 19 and 20. Black arrowhead in Fig. 22 shows an appendage. Black arrows in Figs 18, 23, and 24 indicate laminated outer layer. 25–27. Spores in SEM. Scale bars: 16, 17 = 20 μm, 18–25 = 10 μm, 26, 27 = 2 μm.

FIGURES 28–34. Anthracocystis anadelphiae on Anadelphia pumila (isotype, H.U.V. 15 800). 28, 29. Habit (sori in groups of spikelets are illustrated in Fig. 28, sori in some spikelets of an inflorescence—in Fig. 29). Black arrow in Figs 28 indicates branched columella. 30. Spore balls in LM. 31, 32. Spore balls and spores in LM. In Fig. 31, black arrow indicates inner spores, black arrowhead shows outer spores. 33, 34. Spore balls in SEM. Scale bars: 28 = 5 mm, 29 = 1 mm, 30–32 = 10 μm, 33 = 20 μm, 34 = 5 μm.