Monodictys paradoxa (Corda) S. Hughes, Canad. J. Bot.

Sánchez, Romina M. & Bianchinotti, M. Virginia, 2023, New records of mitosporic ascomycetes on Nothofagaceae from Patagonia, Argentina, Boletin de la Sociedad Argentina de Botanica 58 (4), pp. 491-503 : 497

5. Monodictys paradoxa (Corda) S. Hughes, Canad. J. Bot. 36: 786. 1958. Fig. 2 J-N.

Colonies superficial, discrete, punctate, irregular, dark brown, bright. Mycelium scarce, immerse, hyphae cylindrical, short, flexuous, thick walled, smooth, brown. Conidiophores semi-macronematous, cylindrical, long, smooth, hyaline, ca. 3 µm diam. Conidiogenous cells monoblastic, integrated, terminal, cylindrical, short, sometimes narrowing to the apex, smooth, brown, 5-19 × 4-8 (M = 11.4 × 5.6). Conidia irregular, globose, clavate or pyriform, smooth, dark reddish brown, constricted at the thick septa, 21-49 × 14-36 µm (M = 33.2 × 22.2; n = 47), individual cells globose, guttulate, often 2–4 basal cells lighter. Monosporic isolates were done on NA, NGA and PDA following Goh (1999) and placing groups of conidia over small pieces of sterilized Nothofagus wood. Sporulation was observed at 7 days and formation of yellow crystals appeared in some 4 months old cultures.

Distribution and habitat. Growing on the bark of stems of Lophozonia alpina and L. obliqua in Argentina ; on bark of a dead branch of fallen Sorbus aucuparia L. tree in Belarus ( Yurchenko, 2001); on Betula papyrifera Marshall and Betula sp. from Canada ( Hughes, 1960, 1987); on standing senescent culms of Bambusa sp. and Miscanthus floridulus (Labill.) Warb. ex K. Schum. & Lauterb. in China ( Wong & Hyde, 2001); on Betula sp. in Czech Republic (Corda, 1938); on Nectandra sp. in Cuba ( Mercado Sierra, 1981); on bark of Eucalyptus tereticornis Sm. and Eucalyptus sp. in India ( Prasher & Verma, 2016); Prunus yedoensis Matsum. in Japan ( Matsushima, 1975); on indeterminate bark, twig and decayed wood from Mexico ( Heredia-Abarca, 1998); on dead wood of Betula pendula Roth and Quercus robur L. in Lithuania ( Treigiené & Markovskaja, 2003; Markovskaja & Treigiené 2005); on unidentified wood and bark from Malawi ( Sutton, 1993); on different parts of Rubus gracilis J. Presl & C. Presl and Rubus sp. and bark of Sizyngium cumini (L.) Skeels in Pakistan ( Abbas & Sobia, 2008); on B. pendula and Quercus sp. in Poland ( Kieruczenko, 1976); on stems of Chrysanthemum coreanum (H. Lév. & Vaniot) Nakai ex T. Mori. and cuttings of Rhododendron sp. and branches of R. dauricum L. and R. sichotense Pojark. from Russia ( Melnik & Papushoi, 1992; Melnik 2000; Pavlyuk, 2009); on unidentified twigs in Taiwan ( Matsushima, 1980); on B. pendula in Scotland, Ukraine and United Kingdom ( Hughes, 1951; Hayova, 2011); on wood of Acer saccharum Marshall and Lonicera canadensis Bartram & W. Bartram ex Marshall in the USA ( Barr, 1978; Mack, 2022), and on Glycyrrhiza glabra L. in Uzbekistan ( Gafforov, 2017).

Comments. The specimen found in Patagonia agrees well with the original, just for a slight difference in the size of conidiogenous cells. Species of Monodictys are widely spread around the world. When compared with the only three species previously recorded in South America, M. paradoxa is distinct from M. castaneae (Wallr.) S. Hughes , found on leaves of Eucalyptus spp. in Brazil, because this latter has conidia formed by a few cells, with verrucose walls and truncate base ( Wellbaum et al., 1999). It differs from M. glauca (Cooke & Harkn.) S. Hughes , recorded on bark of Nothofagus betuloides in Tierra del Fuego ( Argentina), due to its smaller conidia (7-14 × 5-10 µm) ( Godeas & Arambarri, 2007). Lastly it could be distinguished from M. pelagica (T. Johnson) E.B.G. Jones , recorded on bark of an indeterminate plant in Chile, for having undifferentiated conidiophores and conidiogenous cells, and slightly smaller conidia that when mature they turn completely black so septa are not visible (34-44 × 17-31 µm) ( Hughes & Chamut, 1971).

Material examined. ARGENTINA. Neuquén: Parque Nacional Lanín, on the way to Lago Hui Hui; 17-V-2007, on bark of L. alpine, Bianchinotti and Sánchez 574 (BBB); ibid., in the path of ascent to Cascada Chachín (40° 8′ 25.29″ S, 71° 40′ 3.84″ W), 757 m alt., 17-V-2007, on bark of L. obliqua, Bianchinotti and Sánchez 592 (BBB).

Figures

Fig. 2. Dwiroopa ramya. A: Stromatic conidioma on decorticated wood. B: Two microconidia surrounded by macroconidia. C: View of the longitudinal germ slits of macroconidia. D: Conidium germinating through the longitudinal slit. Gilmaniella multiporosa. E: Sporodochial conidioma on substrate. F: Conidiophore. G: Conidiogenous cell. H: Conidia in chains. I: Terminal conidia showing multiple scars. Monodictys paradoxa. J: Conidioma on substrate. K: Conidium detached from the conidiogenous cell which narrows towards the apex. L: Conidium showing the lighter basal cells and a rest of the conidiogenous cell. M: Germinating conidium and formation of a new one. N: Different shapes and sizes of conidia. Pycnopeziza quisquiliaris. O: Vertical section of a conidioma. P: Chain of two conidia (phloxine stain). Q: Conidia attached to conidiogenous cells (phloxine stain). R: Conidiophore.Abbreviations= cg: conidiogenous cell; cp: conidiophore; mc: microconidia; s: scars; sl: germ slits. Scale bars= A: 1 mm; B–I, L–N, P: 15 µm; K, Q–R: 10 µm; O: 50 µm.