Spiropes penicillium (Speg.) M.B. Ellis, Mycol. Pap. 114: 23, 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 penicillium (Speg.) M.B. Ellis, Mycol. Pap. 114: 23, 1968

Fig. 20

Podosporium penicillium ≡ Podosporium penicillium Speg., Boln. Acad. nac. Cienc. Córdoba 11: 618, 1889.

Arthrobotryum penicillium ≡ Arthrobotryum penicillium (Speg.) F. Stevens, Bot. Gaz. 65: 238, 1918.

Arthrobotryum strychni = Arthrobotryum strychni Henn., Hedwigia 43: 397, 1904.

Podosporium strychni ≡ Podosporium strychni (Henn.) Cif., Sydowia 9: 311, 1955.

Arthrobotryum glabroides = Arthrobotryum glabroides F. Stevens, Bot. Gaz. 65: 237, 1918.

Podosporium glabroides ≡ Podosporium glabroides (F. Stevens) Cif., Sydowia 9: 309, 1955.

Description.

Colonies effuse, yellowish to dark olivaceous-brown, velvety, with tightly packed hyphae that form large, erect, dark synnemata clearly visible under the stereomicroscope. A bright yellow pigment diffuses out when colonies are mounted in lactic acid or lacto-phenol. Hyphae superficial, branched, septate, 1-2 µm wide, yellowish, pale olive, smooth. Conidiophores tightly packed to form dark brown to blackish synnemata up to 650 µm long, 10-40 µm thick, often splaying out to a width of 100 µm at the apex. Individual hyphae straight or flexuous, cylindrical, 1-2 µm thick near the base, 2-3.5 µm thick near the apex, pale olivaceous-brown, smooth, with numerous small conidial scars. Conidia solitary, fusiform or occasionally almost cylindrical, mostly 3(-5)-septate, 16-23(-37) × (3-)3.5-5(-7) µm, tapering to about 1 µm at the apex and base, middle cells pale brown, the cells at each end paler, surface wrinkled or verruculose. As seen by SEM, the ornamentation of the spores is distinctly reticulated, with thin to thick networks that can form ridges-like structures.

Specimen examined.

On Meliola calva on leaves of Lauraceae , Brasil, S. Paulo, Apiahy, 1881, J. Puiggari 1483 (IMI 131184, type of Podosporium penicillium ); on Meliola sp. on leaves of Oxyanthus sp. ( Rubiaceae ), Sierra Leone, 1951, D.S. Rennis (IMI 51664).

Illustrations.

This species was illustrated by Ellis (1968).

Known hosts and distribution.

On colonies of Asteridiella spp. and Meliola spp. on living leaves of various plants in Brazil, Congo, Costa Rica, Ghana, Ivory Coast, Nigeria, Sierra Leone and Uganda ( Ellis 1968).

Notes.

Spiropes penicillium is easily distinguishable from other known synnematous species of the genus Spiropes by the presence of fusiform to cylindrical conidia without rostra. In addition, a bright yellow pigment diffuses out of the cells when colonies are mounted in lactic acid or lacto-phenol ( Ellis 1968).

Figures

Figure 20. Spiropes penicillium (IMI 51664) a conidiophores with scars (the thickness of the wall is shown on the right-handed drawing) b conidia shown in optical section (first two left-hand drawings) and as seen by SEM c, d as seen by SEM c tips of conidiophores with scars d conidia. Scale bars: 5 μm (a); 2.5 μm (b); 3 μm (c); 5 μm (d).