Spiropes melanoplaca (Berk. & M.A. Curtis) M.B. Ellis, Mycol. Pap. 114: 28, 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 melanoplaca (Berk. & M.A. Curtis) M.B. Ellis, Mycol. Pap. 114: 28, 1968

Fig. 18

Arthrobotryum melanoplaca = Arthrobotryum melanoplaca Berk. & M.A. Curtis, J. Linn. Soc. Bot. 10(46): 360, 1868.

Podosporium melanoplaca ≡ Podosporium melanoplaca (Berk. & M.A. Curtis) Cif., Sydowia 9(1-6): 310, 1955.

Podosporium dialii = Podosporium dialii Bat. [as ' dialiumii '], Atas Inst. Micol. 1: 266, 1960. New synonym proposed in this study.

Spiropes dialii ≡ Spiropes dialii (Bat.) M.B. Ellis, Mycol. Pap. 114: 27, 1968. New synonym proposed in this study.

Arthrobotryum scoparium = Arthrobotryum scoparium Henn., Hedwigia 43(6): 397, 1904. New synonym proposed in this study.

Description.

Colonies effuse, dark brown to black, hairy, with tightly packed hyphae that form large, erect, dark synnemata clearly visible under the stereomicroscope. Hyphae superficial, branched, septate, 1.5-6 µm wide, pale olivaceous, smooth. Conidiophores tightly packed to form dark brown to blackish synnemata up to 1.5 mm high, spreading out at the apex, 20-80 µm thick, splaying out at the apex. Individual hyphae straight or flexuous, cylindrical, 2-6 µm thick along most of their length, 5-8 µm thick near the apex, with numerous small scars that may overlap like scales. As evident by SEM, the scales are produced by the peeling of the outer wall layers where the scars are located. Conidia straight or curved, fusiform to obclavate, 3-septate, (30-)40-52(-68) × (7-)9-11(-14) µm, with the two middle cells usually golden brown or brown, warty and the cells at each end paler. As seen by SEM, the ornamentation of the spores is distinctly reticulated, with thin to thick networks and no ridges.

Specimens examined.

On Meliola mangiferae on living leaves of Mangifera indica ( Anacardiaceae ), Panama, Chiriquí Province, Los Algarrobos, 8°31'05"N, 82°25'25"W, 168 m a.s.l., 20 January 2020, M. A. Bermúdez-Cova, MB81; same fungal and plant host, Panama, Chiriquí Province, Universidad Autónoma de Chiriquí (UNACHI), 8°25'57"N, 82°27'02"W, 37 m a.s.l., 23 January 2020, M. A. Bermúdez-Cova, MB85 (UCH15487); same fungal and plant host, Panama, Chiriquí Province, Los Algarrobos, Majagua River Trail , 8°28'56"N, 82°24'47"W, 101 m a.s.l., 23 January 2020, M. A. Bermúdez-Cova, MB89 (UCH15488, M); same fungal and plant host, Panama, Chiriquí Province, Meseta de Chorcha , 8°24'19"N, 82°13'26"W, 94 m a.s.l., 16 February 2020, M. A. Bermúdez-Cova, A. Sanjur, MB101 (UCH); same fungal and plant host, Panama, Chiriquí Province, Boqueron District , Hidroeléctrica Chuspa, 8°33'37"N, 82°36'22"W, 331 m a.s.l., 6 March 2020, M. A. Bermúdez-Cova, A. Sanjur, S. Samaniego, MB119 (UCH15491); On Meliola sp. on living leaves of Angylocalyx oligophyllus ( Fabaceae ), Benin, Attogon, Niaouli, Niaouli Forest , 6°44'42"N, 2°7'50"E, 69 m a.s.l., 28 February 2022, M.A. Bermúdez-Cova, A. Tabé, I. Agonglo, O.P. Agbani, M. Piepenbring, N.S. Yorou, MB173 (M); on Meliola mangiferae on living leaves of Mangifera indica , Benin, Attogon, Niaouli, Niaouli Forest , 6°44'44"N, 2°7'49"E, 65 m a.s.l., 28 February 2022, M.A. Bermúdez-Cova, A. Tabé, I. Agonglo, O.P. Agbani, M. Piepenbring, N.S. Yorou, MB180 (M) .

Additional specimens examined.

On Meliola mangiferae on Mangifera indica , Brunei, 1974, W.T.H. Peregrine (IMI189570a); on Meliola sp. on Psychotria sp. ( Rubiaceae ), Cuba, 1879, C. Wright (IMI 105348 and IMI 105349, syntypes of Arthrobotryum melanoplaca ) .

Illustrations.

This species was illustrated by Ellis (1968).

Known hosts and distribution.

On colonies of Meliolales , especially Meliola spp., on living leaves of various plants in Brazil, Cuba, China, Dominican Republic, Ghana, Guadalcanal, India, Malaysia, Peru, Philippines, Sierra Leone, Tanzania, Trinidad and Uganda ( Ellis 1968; Zhao et al. 1996; Dubey and Moonnambeth 2013). Spiropes melanoplaca is reported here for the first time for Benin and Panama.

Notes.

According to Ellis (1968), the main difference between Spiropes melanoplaca and S. dialii is the range of spore width, with S. melanoplaca having wider spores (9-14 µm wide) than S. dialii (7-9 µm wide). However, after revision of several specimens and herbarium material from both species, we noticed that the aspect of the colonies, morphological features (both as seen in LM and by SEM) are similar between the species and both species present conidia with a similar size range (Fig. 15 ). Therefore, we propose S. dialii as a synonym of S. melanoplaca .

Figures

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

Figure 18. Spiropes melanoplaca (MB 81, MB 119, IMI 189570 a) a, b synnemata growing on hyphae of Meliola mangiferae on living leaves of Mangifera indica c conidiophores with scars and young conidia shown in optical section. The thickness of the wall is only shown in the first conidiophore, from left to right d conidia, shown in optical section (left-hand drawing) and as seen by SEM (right-hand drawing) e, f as seen by SEM e parts of conidiophores with scars f conidium. Scale bars: 1.5 mm (a); b); 0.9 mm (c); 8 μm (d); 7 μm (e); 8 μm (f).