Ceratocystiopsis weihaiensis R.L. Chang & X.Y. Zhang, 2021

Chang, Runlei, Zhang, Xiuyu, Si, Hongli, Zhao, Guoyan, Yuan, Xiaowen, Liu, Tengteng, Bose, Tanay & Dai, Meixue, 2021, Ophiostomatoid species associated with pine trees (Pinus spp.) infested by Cryphalus piceae from eastern China, including five new species, MycoKeys 83, pp. 181-208 : 181

2. Ceratocystiopsis weihaiensis R.L. Chang & X.Y. Zhang sp. nov.

Fig. 10

Holotype.

China. Shandong province: Zhujiajuan village, Huancui District, Weihai City, from the gallery of Cryphalus piceae on Pinus thunbergii , 2 Sep. 2019, R. L. Chang (HMAS 249923-holotype; SNM649 = CGMCC3.20246 - ex-holotype culture).

Additional cultures checked.

China. Shandong province: Zhujiajuan village, Huancui District, Weihai City, from the gallery of Cryphalus piceae on Pinus thunbergii , 2 Sep. 2019, R. L. Chang (SNM634).

Etymology.

The name refers to Weihai City, where this fungus was isolated.

Diagnosis.

Compared to other closely related species, the conidia of C. weihaiensis are smaller.

Description.

Sexual morph is unknown. Asexual state hyalorhinocladiella-like: the conidiophores directly arise singly from the vegetative hyphae, measuring (2.6-) 10.9-29.2 (-44.6) μm × (0.7-) 0.9-1.3 (-1.6) μm (Fig. 10b-e ); conidia hyaline, smooth, unicellular short oblong, with rounded ends or clavate, ellipsoidal to ovoid measuring (1.5-) 2.0-2.6 (-2.9) × (0.7-) 0.9-1.2 (-1.5) μm (Fig. 10b-e ).

Culture characteristics.

The colonies are light brown in color on MEA (Fig. 10a ). Mycelia white, submerged in the agar. The optimal temperature for growth is 30 °C, reaching 46.0 mm diam in 10 days. Growth is slower at 35 °C, 27 mm diam in 10 days.

Distribution.

Currently known from Weihai City in Shandong Province, China.

Note.

Ceratocystiopsis weihaiensis is phylogenetically close to C. minuta , but formed a distinct monophyletic clade on both ITS and BT trees (Figs 1 and 2 ). In the phylogenetic study of C. minuta by Plattner et al. (2009) using ITS, LSU, and BT gene regions, the authors suggested that this taxon is possibly an assemblage of multiple species. Therefore, they designated the strain RJ705 from Poland as the neotype. Later, strain RJ705 = UAMH 11218 = WIN(M) 1532 was considered as the lectotype for C. minuta ( Reid and Hausner 2010).

Ceratocystiopsis minuta and most other Ceratocystiopsis species have a hyalorhinocladiella-like asexual state ( Plattner et al. 2009; De Beer and Wingfield 2013). The conidia of C. weihaiensis and C. minuta are similar in gross morphology. The C. weihaiensis differs from C. minuta in having short conidia size (1.5-2.9 × 0.7-1.5 vs. 2-4 × 1-2 μm, Fig. 10b-e ) ( Reid and Hausner 2010).

Figures

Figure 1. Maximum likelihood phylogeny of Ceratocystiopsis using complete ITS and partial BT gene regions. The isolates recovered in this study are highlighted in color and in bold font. ML and MP bootstrap support values ≥ 75 are indicated at the nodes as ML / MP. Bold branches indicate posterior probabilities values ≥ 0.9. T indicates ex-type cultures.

Figure 2. Maximum likelihood phylogeny of Ceratocystiopsis using partial LSU gene regions. The isolates recovered in this study are highlighted in color and in bold font. ML and MP bootstrap support values ≥ 75 are indicated at the nodes as ML / MP. Bold branches indicate posterior probabilities values ≥ 0.9. T indicates ex-type cultures.

Figure 10. Morphological characters of asexual structures of Ceratocystiopsis weihaiensis sp. nov a fourteen-day-old culture on MEA b-e conidiophores and conidia. - Scale bars: 10 μm.