Diplodia alanphillipsii Abdollahz. & A. Javadi, sp. nov.

Index Fungorum number: IF 557831; MycoBank number: MB 557831; Facesoffungi number: FoF 09953; Fig. 1

Etymology – Named after Dr. Alan J.L. Phillips for his extensive, qualitative and valuable research on the systematics of the Botryosphaeriaceae.

Holotype – IRAN 14273F

On twigs of Citrus sp. Sexual morph Undetermined. Asexual morph Conidiomata pycnidial, solitary or clustered, immersed in the host or partially erumpent, globose, dark brown to black, ostiolate, apapillate, unilocular, thick-walled with outer dark brown layers and inner thin-walled hyaline textura angularis. Paraphyses not observed. Conidiophores reduced to conidiogenous cells or with a supporting cell. Conidiogenous cells hyaline, thin-walled, smooth, cylindrical, swollen at the base, discrete, enteroblastic, annellidic, indeterminate, often proliferating internally giving rise to periclinal thickenings or proliferating percurrently forming 2–3 annellations. Conidia (17–)20–22(–26)×(8–)10–11(–13.5) µm (av.±SD =21.5±1.5×10.5±0. 8 μm, l/w ratio=2.2±0.2), aseptate, ovoid, widest in the middle, obtuse at the apex, truncate or rounded at the base, initially hyaline, becoming dark brown before release from the pycnidium, moderately thick-walled, externally smooth, roughened on the inner surface.

Material examined – IRAN, Hormozgan Province, Minab, Hajikhademi, on twigs of Citrus sp., 3 March 2007, J. Abdollahzadeh and A. Javadi (IRAN 14273F, holotype), extype living culture, IRAN 1508C=CBS 124713; Rodan, on twigs of Mangifera indica, 3 March 2007, J. Abdollahzadeh and A. Javadi, IRAN 1509C; on twigs of Citrus sp., 3 March 2007, J. Abdollahzadeh and A. Javadi, IRAN 1574C=CBS 124712.

GenBank numbers – IRAN 1508C: ITS = KF890208, TEF1-α = KF890190; IRAN 1509C: ITS = KF890209, TEF1-α = KF890191; IRAN 1574C: ITS = MT258875; TEF1-α=MT270153.

Notes – Diplodia alanphillipsii is close to D. citricarpa with 4 base pairs differences in ITS (3 substitutions, 1 deletion/insertion) and one in TEF1-α (substitution), but can be distinguished due to the relatively smaller conidia when compared to D. citricarpa (22–25×9–10 μm) (Yang et al. 2017b). These two species are also differentiated based on the ISSR (data not shown) and rep-PCR fingerprinting patterns (Abdollahzadeh and Zolfaghari 2014). Sequences generated for D. citricarpa were deposited in GenBank: IRAN 1578C = CBS 124715 (ITS: KF890207; TEF1-α: KF890189); IRAN 1511C (ITS: KF890206; TEF1-α: KF890188); IRAN 1510C (ITS: MT258874; TEF1-α: MT270152).

Figure 1 –  Diplodia alanphillipsii (IRAN 14273F, holotype). a Conidiomata on pine needles in culture. b Hyaline immature conidia developing on conidiogenous cells. c, d Conidiogenous cells with periclinal thickenings or annellations. e Brown aseptate conidia on conidiogenous cells. f Mature brown conidia. g, h Mature conidia in two different focal planes. Scale bars: a=500 μm, b–f=5 μm, g, h=10 μm