Dothiorella baihuashanensis L. Lin & X.L. Fan, 2023

Lin, Lu, Bai, Yukun, Pan, Meng, Tian, Chengming & Fan, Xinlei, 2023, Morphology and molecular analyses reveal three new species of Botryosphaeriales isolated from diseased plant branches in China, MycoKeys 97, pp. 1-19 : 1

Dothiorella baihuashanensis L. Lin & X.L. Fan sp. nov.

Fig. 5

Etymology.

Named after the collection site of the type specimen, Baihuashan Natural Scenic Area in Beijing City.

Description.

Conidiomata pycnidial, superficial or immersed, separate, ovoid, 350-500 µm in diam, occasionally aggregated into botryose clusters. Disc black, 200-300 µm in diam. Ostioles single, central, papillate. Conidiophores reduced to conidiogenous cells. Conidiogenous cells hyaline, holoblastic, cylindrical to subcylindrical or broadly lageniform, 7.5-16.0 × 3.5-6.5 μm (av. ± S.D. = 11.7 ± 2.2 × 4.6 ± 0.7 μm). Conidia1-septate, hazel to blackish brown, mostly truncate at the base and constricted at the septum or with a thickening at the base of the septum, moderately thick-walled, ovoid or oblong to ellipsoidal, 22.5-35.0 × 11.0-19.0 μm (av. ± S.D. = 27.9 ± 2.9 × 14.3 ± 2.2 μm).

Culture characters.

Colonies on PDA spreading, covering a 90 mm plate after 14 days at 25 °C, upper white to pale grey, reverse buff to dark grey. Colonies on MEA spreading, covering a 90 mm plate after 14 days at 25 °C, uniform with appressed aerial mycelium and crenate edge, upper white to pale grey, reverse honey to dark grey.

Materials examined.

China, Beijing City, Mentougou District , Qingshui County, Baihuashan Natural Scenic Area , 39°50'18.21"N, 115°34'21.13"E, on dead branches of Juniperus chinensis , 23 August 2022, Lu Lin & Xinlei Fan (holotype BJFC CF20230107, ex-holotype culture CFCC 58549); 39°50'18.16"N, 115°34'21.24"E, on dead branches of Juniperus chinensis , 23 August 2022, Lu Lin & Xinlei Fan (paratype BJFC CF20230108, ex-paratype culture CFCC 58788) .

Notes.

The isolates CFCC 58549 and 58788 in this study formed a distinct linage in the phylogenetic trees of each individual gene (ITS, tef1 -α, and tub2) and the combined gene dataset (Fig. 2 ). They were isolated from the branches Juniperus chinensis . Dothiorella iberica was also recorded to host genus Juniperus ( Alves et al. 2013). However, these two species are not closely related in our phylogenetic analysis.

Figures

Figure 2. Phylogram of Dothiorella resulting from a maximum likelihood analysis based on combined ITS, tef 1 and tub 2 loci. Numbers above the branches indicateML bootstrap values (ML-BS ≥ 70 %) and Bayesian Posterior Probabilities (BPP ≥ 0.9). The tree is rooted with Lasiodiplodia americana CFCC 50065. Ex-type isolates are in bold. Isolates from the present study are marked in blue.

Figure 5. Dothiorella baihuashanensis (BJFC CF 20230107) A, B habit of conidiomata on twig C transverse section of a conidioma D longitudinal section through a conidioma E, F conidiogenous cells G conidia H colony on PDA at 14 days I colony on MEA at 14 days. Scale bars: 1 mm (A); 200 µm (B-D); 10 µm (E-G).