Vandijckomycella snoekiae Hern.-Restr., L. W. Hou, L. Cai & Crous, 2020

Hou, Lingwei, Hernandez-Restrepo, Margarita, Groenewald, Johannes Zacharias, Cai, Lei & Crous, Pedro W., 2020, Citizen science project reveals high diversity in Didymellaceae (Pleosporales, Dothideomycetes), MycoKeys 65, pp. 49-99 : 49

Vandijckomycella snoekiae Hern.-Restr., L. W. Hou, L. Cai & Crous sp. nov. Figure 12

Etymology.

snoekiae refers to Rana Marit Ida Snoek who collected the soil sample from which the ex-type strain was isolated.

Typus.

The Netherlands. Utrecht province, Utrecht, isolated from garden soil, Mar. 2017, R.M.I. Snoek (holotype designated here CBS H-24111, living ex-type culture CBS 144954 = JW 149017).

Conidiomata pycnidial, superficial on the agar or covered under a thick mycelial layer, scattered or aggregated, mostly solitary, globose to subglobose, sometimes confluent, ellipsoidal, dark brown, covered by abundant long hyphal outgrowths, 150-650(-850) × 145-600(-730) μm; ostioles inconspicuous; pycnidial wall pseudoparenchymatous, 5-9 layers, 37-58.5 μm thick, outer layers composed of brown, flattened polygonal cells, 10-23 μm diam. Conidiogenous cells phialidic, hyaline, smooth, globose, ampulliform or lageniform, 5-8.5 × 5-7.5 μm. Conidia oblong, smooth- and thin-walled, hyaline, aseptate, 4-6.5 × 2-2.5 μm, with two small polar guttules. Conidial matrix whitish.

Culture characteristics.

Colonies after 7 d at 25 °C, on OA reaching 50-55 mm diam after 7 d, covered by floccose aerial mycelium, pink to grey, darker grey near the centre, margin regular; reverse black near the centre, yellow towards the periphery. On MEA reaching 50-55 mm diam, aerial mycelium floccose to cottony, buff with some mouse grey zones, margin regular; reverse orange with some radial yellow lines and some black zones. On PDA, reaching 45-50 mm diam, covered by floccose aerial mycelium, vinaceous grey to pale olivaceous, olivaceous grey near the centre, margin irregular; reverse buff to orange, black near the centre. NaOH spot test on OA: pale reddish discolouration.

Notes.

Morphologically, V. snoekiae differs from its closest phylogenetic neighbour V. joseae in the size of its pycnidia and the number of ostioles. Vandijckomycella snoekiae produces larger pycnidia with inconspicuous ostioles, measuring 150-650(-850) × 145-600(-730) μm, while V. joseae produces pycnidia with 1-2 ostioles, measuring 150-340 × 130-250 μm. In addition, V. snoekiae produces conidia with less and smaller guttules than V. joseae (2 guttules, vs. 1-3 large guttules).

Figures

Figure 12. Vandijckomycella snoekiae (CBS 144954). A, B Colony on OA (front and reverse) C, D colony on MEA (front and reverse) E, F colony on PDA (front and reverse) G, H pycnidia forming on OA I, J section of pycnidial wall K-N conidiogenous cells O conidia. Scale bars: 100 μm (H); 50 μm (I); 10 μm (J); 5 μm (K-O).