Ceratocystiopsis pseudoweihaiensis D. Xie, H. W. Chen & D. F. Chi, 2025

Xie, Dan, Chen, Huanwen, Jia, Niya, Niu, Fang, Wang, Xiaomei, Yu, Jia & Chi, Defu, 2025, Ophiostomatoid fungi associated with Hylurgus ligniperda, including six new species from eastern China, IMA Fungus 16, pp. e 169382-e 169382 : e169382-

Ceratocystiopsis pseudoweihaiensis D. Xie, H. W. Chen & D. F. Chi sp. nov.

Fig. 8

Etymology.

The epithet pseudoweihaiensis (Latin) refers to the morphological resemblance and phylogenetic affinities with Ceratocystiopsis weihaiensis .

Diagnosis.

Ceratocystiopsis pseudoweihaiensis is phylogenetically distinct from all morphologically similar species, from which it can be readily distinguished using molecular sequence data for the beta-tubulin ( βT) and the elongation factor 1 - alpha ( TEF 1 - α) regions (Suppl. materials 4, 5).

Type.

China • Shandong Province: Yantai City , from Hylurgus ligniperda , Nov. 2022, Dan Xie ( holotype HMAS 354192 , dried culture prepared from NFF 1617 ; ex-holotype culture CGMCC 3.28600 = NFF 1617 ) .

Description.

Sexual morph not observed. Asexual morph observed mononematous. Mononematous morph: hyalorhinocladiella-like, conidiogenous cells arising directly from mycelium, (3.5 –) 6–52 (– 87) × (0.5 –) 1–1.5 (– 2) μm; conidia hyaline, smooth, unicellular short oblong, with rounded ends or clavate, (1.5 –) 2–3 (– 3.5) × (0.5 –) 1–1.5 (– 2) µm.

Culture characteristics.

The colonies are white in color on 2 % MEA, hyphae submerged in agar with aerial mycelium. The optimal temperature for growth is 25–30 ° C, reaching 63 mm diam in 15 days. Slow growth at 5 ° C and 35 ° C, growth diameter of 11 mm and 15 mm in 15 days.

Ecology.

Isolated from migratory beetles living in Pinus hosts. Insect vector: H. ligniperda .

Distribution.

Currently known only from Shandong Province, China.

Additional specimens examined.

China • Shandong Province: Yantai City , from H. ligniperda , Nov. 2022, D. Xie (living culture NFF 1616 ) .

Notes.

Phylogenetic analyses showed that C. pseudoweihaiensis is a close relative of C. weihaiensis . However, several morphological differences separate them. Ceratocystiopsis weihaiensis produces light brown colonies, while those of C. pseudoweihaiensis are white. The key distinguishing feature is the length of the conidiogenous cells, which are significantly longer in C. pseudoweihaiensis (6–52 μm) than in C. weihaiensis (10.9–29.2 μm) ( Chang et al. 2021). Based on both phylogenetic and morphological evidence, we propose C. pseudoweihaiensis as a novel species.

Figures

Figure 8. Morphological characteristics of Ceratocystiopsis pseudoweihaiensis sp. nov. (NFF 1617). a. Fifteen-day-old culture on 2 % MEA; b – e. Hyalorhinocladiella-like asexual morph: conidiogenous cells and conidia. Scale bars: 20 μm (b – e).