Diaporthales » Schizoparmaceae » Coniella

Coniella malaysiana

Coniella malaysiana L.V. Alvarez & Crous, in Alvarez, Groenewald & Crous, Stud. Mycol. 85: 21 (2016)                                                                                                              

Index Fungorum number: IF 817823, Facesoffungi number: FoF 14882

Associated with leaf spots of Jasminum sp. Leaf spots irregular or oval to elongated, brown, surrounded by a dark brown to black margin, outermost surrounding reddish brown. Sexual morph: Not observed. Asexual morph: Coelomycetous. Conidiomata 135–140 μm diam., 100–130 μm high (= 139 × 114 μm, n = 5), pycnidial, semi-immersed, sometimes erumpent, solitary, scattered or gregarious, uniloculate, globose to subglobose, black. Conidiomata wall 13.5–24.5(–28) μm diam. (= 18.6 μm, n = 10), consisting of 3–4 layers of thick-walled pseudoparenchymatous cells of textura angularis, outer layers dark brown, inner layer pale brown to hyaline. Conidiophores 6.9–15 μm long (= 11.2 μm, n = 10), straight to flexuous, cylindrical to ampulliform or oblong, hyaline, aseptate, unbranched, sometimes reduced to conidiogenous cells. Conidiogenous cells enteroblastic, phialidic, 6.9–13 × 2.1–3.4 μm (= 10.7 × 2.6 μm, n = 10), hyaline, cylindrical or ampulliform, guttulate, smooth-walled. Conidia (7.5–)8.2–13.1 × 4–5 μm (= 10.6 × 4.1 μm, n = 50), hyaline when immature, becoming pale to dark brown upon maturation, guttulate, aseptate, smooth, thick-walled, 0.4–1.5 μm diam. (= 0.75 μm, n = 30), fusiform to truncate to sub-ellipsoidal, sometimes obovoid, wider in the middle, tapering towards a slightly curved apex and base, often with a prominent protruding basal hilum. Appressoria 19–23 × 9–15 μm (= 20.9 × 12 μm, n = 2), single-celled, sub-ellipsoidal to irregular-shaped, hyaline.

Culture characteristics: Colonies on MEA reaching approximately 20 mm diam. after 7 days of incubation at 25 °C, elevation flat or raised, round with raised margin, forming concentric rings, mycelium dense and aerial, white.

Material examined: Thailand, Chiang Mai Province, Omkoi district, Yang Piang sub-district, associated with leaf spots of Jasminum sp. (Oleaceae), 16 October 2019, D. Gomdola, DG392 (MFLU 23-0389), living culture MFLUCC 23-0240.

Hosts and Distribution: Leaves of Corymbia torelliana in Malaysia (Alvarez et al. 2016), leaves of Jasminum sp. in Thailand (this study).

GenBank accession numbers: ITS = OR608286, 28S = OR608334, Rpb2 = OR601568 and tef-1α = OR601569.

Notes: Our collection shares similar morphological characters with those of the ex-type, C. malaysiana (CBS 141598) (Alvarez et al. 2016). Our strain and C. malaysiana (CBS 141598) have hyaline to brown, aseptate conidia with guttules (Alvarez et al. 2016). Conidial sizes are mostly similar (Table 1). The conidial length-to-width ratio of our isolate is 2.6, and that of C. malaysiana (CBS 141598) is 2.5. Other morphological similarities and differences between the two strains of C. malaysiana are given (Table 1).

In the phylogenetic analyses of the combined ITS, 28S, Rpb2, and tef-1α, our isolate is sister to the ex-type of C. malaysiana (99% ML-IQ, 100% MP, 1.00 PP) (Figure 2). Excluding gaps in our aligned untrimmed dataset, upon comparison of the intra-species genetic distance between our strain and the ex-type of C. malaysiana, the following differences were observed: 0.55% across ITS (553 nucleotide base pairs, bp), 0.12% across 28S (827 bp), 0.26% across Rpb2 (767 bp), but 2.4% across tef-1α (295 bp).

Based on morphology and multigene phylogenetic analyses, we identify our strain as a new host record of Coniella malaysiana, associated with leaf spots of Jasminum sp. in northern Thailand.