Spiropes intricatus (Sacc.) M.B. Ellis, Mycol. Pap. 114: 9, 1968

Bermudez-Cova, Miguel A., Hofmann, Tina A., Yorou, Nourou S. & Piepenbring, Meike, 2024, Systematic revision of species of Atractilina and Spiropes hyperparasitic on Meliolales (Ascomycota) in the tropics, MycoKeys 103, pp. 167-213 : 167

Spiropes intricatus (Sacc.) M.B. Ellis, Mycol. Pap. 114: 9, 1968

Fig. 14

Brachysporium intricatum ≡ Brachysporium intricatum Sacc., Atti Accad. scient. Veneto-trent.-istriana, Ser. 3, 10: 88, 1919.

Spiropes pirozynskii = Spiropes pirozynskii M.B. Ellis, Mycol. Pap. 114: 19, 1968. New synonym proposed in this study.

Description.

Colonies effuse, straw-coloured, olive or olivaceous-brown, velvety or hairy. Hyphae superficial, branched, anastomosing, septate, 1-2 µm wide, pale olivaceous brown, smooth. Conidiophores arising singly or in groups, terminally or laterally from the hyphae, erect or ascending, straight or flexuous, septate, up to 900 µm long, 2-5 µm thick along most of their length, swollen to 4-9 µm towards the apex and in intercalary parts that produce conidia, pale olivaceous-brown to brown, reticulate as seen by SEM, with scattered cylindrical scars. Conidia solitary, straight or slightly curved, oblong-ellipsoid or obovate to clavate, truncate at the base, mostly 3-septate, (13-)16-23(-25) × (4.5-)6-8 µm, 1.5-3 µm wide at the base, the cells at each end of a conidium pale brown, intermediate cells brown, ornamented. As seen by SEM, the ornamentation of the spores is distinctly reticulated, with thin to thick networks that can form ridges.

Specimens examined.

On Irenopsis sp. on Lindackeria bukobensis ( Achariaceae ), Tanzania, Kigoma, 1964, K.A. Pirozynski M418 b&c (IMI 106645b-c, type of Spiropes pirozynskii ); on leaves of Camellia drupifera ( Theaceae ), Nepal, Kathmandu, Godawari, 1986, U. Budathoki KU294 (IMI323287) .

Illustrations.

This species was illustrated by Ellis (1968).

Known hosts and distribution.

On colonies of Meliolales on living leaves of various plants in Ghana, Philippines and Tanzania ( Ellis 1968).

Notes.

Spiropes intricatus and S. deightonii are the only known species of the genus that present conidiophores that swell in the areas where conidia are formed (Figs 9 , 14 ; Ellis (1968)). Spiropes deightonii differs from S. intricatus by the presence of smaller conidia (12-14 µm long) that are more obovate or clavate rather than oblong-ellipsoid. The type specimen of S. pirozynskii (IMI 106645b-c) is morphologically similar to S. intricatus . Both species present oblong-ellipsoid conidia with a similar size range (Fig. 15 ). Therefore, we propose S. pirozynskii as a synonym of S. intricatus .

Figures

Figure 9. Spiropes deightonii (IMI 48956 a) a conidiophores b conidia, as seen by LM (two upper spores; the thickness of the wall is indicated only in the drawing on the left-hand side) and by SEM (bottom spore) c, d as seen by SEM c conidiophore d conidia. Scale bars: 5 μm (a, b); 8 μm (c); 5 μm (d).

Figure 14. Spiropes intricatus (IMI 106645 b-c) a conidiophores, growing on a hypha of Irenopsis sp., shown in optical section b conidia shown in optical section (the thickness of the wall is indicated only in the drawings on the upper row) and as seen by SEM (second row right) c, d as seen by SEM c conidiophore with scars d conidium. Scale bars: 5 μm (a); 3 μm (b); 7 μm (c); 8 μm (c).

Figure 15. Scatter plot of spore size (width and length) of species of Spiropes.