Neoarthrinium lithocarpicola Ning Jiang sp. nov.

Fig. 2

Etymology.

Named for its host genus " Lithocarpus " and "- cola " = inhabiting.

Description.

Hyphae 1.5-4.5 μm diam., hyaline, branched, septate. Asexual morph: Conidiophores cylindrical, septate, verrucose, flexuous, sometimes reduced to conidiogenous cells. Conidiogenous cells erect, blastic, aggregated in clusters on hyphae, hyaline to pale brown, smooth, globose to subglobose, branched, (4-)5.5-8 × 2.5-3.5(-4) μm, mean ± SD = 6.6 ± 1.3 × 3.1 ± 0.4 μm, n = 50. Conidia brown to dark brown, smooth to finely roughened, subglobose to lenticular, with a longitudinal germ slit, occasionally elongated to ellipsoidal, (5-)6-8(-8.5) × (4.5-)5-5.5(-6) μm, mean ± SD = 7 ± 0.8 × 5.3 ± 0.5 μm, L/W = 1.1-1.8, n = 50. Sexual morph: Undetermined.

Culture characters.

Colonies on PDA flat, spreading, with flocculent aerial mycelium forming concentric rings, edge entire, mouse grey to greyish-green, reaching 60 mm diam. after 10 d at 25 °C, forming abundant conidiomata.

Specimens examined.

China. Guangdong Province, Guangzhou City, on leaf spots of Lithocarpus glaber (Thunb.) Nakai, Shang Sun (holotype CAF800050 = JNH0046; ex-type living culture: CFCC 54456; other living culture: CFCC 55883) .

Notes.

Two isolates of Neoarthrinium lithocarpicola from Lithocarpus glaber (Thunb.) Nakai formed a well-supported monophyletic clade, distinct from N. moseri, N. trachycarpi and N. urticae (Fig. 1). Morphologically, N. lithocarpicola is distinguished from N. moseri in smaller conidia (5-8.5 × 4.5-6 µm in N. lithocarpicola vs. 10-14 × 3-4.5 µm in N. moseri; Gams 1995). Neoarthrinium lithocarpicola is different from N. urticae by lacking thick blackish septa in conidiophores (Ellis 1965). Neoarthrinium lithocarpicola is similar to N. trachycarpi in the size of its conidiogenous cells and conidia, but it can be distinguished by its globose to subglobose conidiogenous cells (Yan et al. 2019).