Diaporthe brideliae L. Schweizer, C. Lamb. & Y. Marin, 2023

Lambert, Christopher, Schweizer, Lena, Matio Kemkuignou, Blondelle, Anoumedem, Elodie Gisele M., Kouam, Simeon F. & Marin-Felix, Yasmina, 2023, Four new endophytic species of Diaporthe (Diaporthaceae, Diaporthales) isolated from Cameroon, MycoKeys 99, pp. 319-362 : 319

Diaporthe brideliae L. Schweizer, C. Lamb. & Y. Marin sp. nov.

Fig. 4

Etymology.

Name refers to the host genus that this fungus was isolated from, Bridelia .

Description.

Conidiomata pycnidial in culture on PNA, globose or irregular, dark brown to black, solitary or in groups, embedded, erumpent, 240-500 μm diam, white to cream or yellow conidial drops exuded from ostioles; conidiomatal wall pale olivaceous green to brown, composed of 1-3 layers, textura angularis. Conidiophores cylindrical to subcylindrical, base pale olivaceous to pale yellow, apex hyaline to subhyaline, straight, densely aggregated, smooth-walled, aseptate or 1(-2) septate, (6-)12-22.5 × 1-3 μm. Conidiogenous cells phialidic, cylindrical, tapering towards the apex, hyaline, mostly terminal, rarely lateral, (7-)8-15.5 × 1-3 μm. Paraphyses not observed. Alpha conidia ovoid to ellipsoidal, hyaline, apex acutely rounded, base acutate, biguttulate, aseptate, (3-)4-6.5 × 1.5-2.5 μm. Beta conidia filiform, curved, tapering towards apex, hyaline, not guttulate, aseptate, 18-32.5 × 1-2 μm. Gamma conidia not observed.

Culture characters.

Colonies on PDA covering the surface of the Petri dish in 2 weeks, grayed white (156B-C) with a grayed orange (174B) ring and grayed orange (163A) margins, velvety to cottony, flat to raised in some zones, margins filamentous to fimbriate; reverse center gray brown (199A) with a yellow orange or grayed orange (167A) zones. Colonies on MEA covering the surface of the Petri dish in 2 weeks, yellow green (153B) with white to grayed yellow (160C) margins, velvety to cottony, flat to raised in some zones, margins filamentous to fimbriate; reverse black (202A) with gray brown (199A) mycelia and yellow green (153B) margins. Colonies on OA covering the surface of the Petri dish in 2 weeks, grayed green (198B) to white mycelium with a yellow green (151B) ring, cottony, flat to raised in some zones, margins filamentous; reverse yellow green (153B) with grayed yellow (161C) margins.

Specimen examined.

Cameroon, Kala Mountain, from Bridelia ndellensis , 03 Jan. 2019, S.C.N. Wouamba (holotype: CBS H-24921, culture ex-type CBS 148911 = STMA 18286).

Notes.

Diaporthe brideliae is the only report in Bridelia ( Phyllanthaceae ) from Cameroon. The phylogenetically most related species are D. chinensis , D. siamensis and D. yunnanensis . Diaporthe chinensis can be distinguished by the absence of beta conidia, which are produced by the other three species. Diaporthe siamensis is the only species mentioned here that produces gamma conidia ( Udayanga et al. 2012b). Diaporthe brideliae can be distinguished from D. yunnanensis by the production of smaller conidiomata (up to 500 μm diam in D. brideliae vs. 880 μm diam in D. yunnanensis ).

Figures

Figure 4. Diaporthe brideliae (ex-type strain CBS 148911) A conidioma in PNA B conidiomata in OA C conidiophores and conidia D alpha and beta conidia. Scale bars: 100 μm (A); 500 μm (B); 5 μm (C, D).