Diversity, pathogenicity and two new species of pestalotioid fungi (Amphisphaeriales) associated with Chinese Yew in Guangxi, China Author Wang, Yifeng https://orcid.org/0009-0006-6533-6615 Beijing Key Laboratory for Forest Pest Control, Beijing Forestry University, Beijing 100083, China Author Tsui, Kin-Ming https://orcid.org/0000-0001-5129-1037 National Centre for Infectious Diseases, Tan Tock Seng Hospital, Singapore 308433, Singapore & Faculty of Medicine, University of British Columbia, Vancouver, V 6 T 1 Z 3, Canada Author Chen, Shimei https://orcid.org/0009-0000-9862-9453 Beijing Key Laboratory for Forest Pest Control, Beijing Forestry University, Beijing 100083, China Author You, Chongjuan https://orcid.org/0000-0001-6130-5703 Beijing Key Laboratory for Forest Pest Control, Beijing Forestry University, Beijing 100083, China chongjuanyou@bjfu.edu.cn text MycoKeys 2024 2024-02-27 102 201 224 http://dx.doi.org/10.3897/mycokeys.102.113696 journal article http://dx.doi.org/10.3897/mycokeys.102.113696 1314-4049-102-201 86674352E59B513ABE2F03A64B2F2AEB Pestalotiopsis taxicola Y. F. Wang & C. J. You sp. nov. Fig. 5 Etymology. Named after the host species, Taxus chinensis . Holotype. BJFC-S1954. Conidiogenesis. Conidiophores reduced to conidiogenous cells, indistinct. Conidiogenous cells were discrete, ampulliform, thin-walled, hyaline, smooth. Conidia fusiform to clavate, straight or slightly curved, olivaceous to brown, 4-septate, 16.5-21 x 4-6 μm , with apical and basal appendages. Basal cell obconic, hyaline, thin-walled, smooth, 2.5-4 µm ; the three median cells dolioform, versicolor, pale brown to brown with septa darker than the rest of the cells, 10.5-12 µm , the second cell from base 3-4 µm ; the third cell 3.5-4 µm ; the fourth cell 3.5-4 µm ; apical cell 2.5-4 µm , cylindrical, hyaline; 3 tubular apical appendages, arising from the apex of the apical cell each at a different point, filiform, 9.5-15 µm ; basal appendage present most of the time, single, tubular, unbranched, 2-5 µm (Fig. 5c-e ). Sexual morph not observed. Figure 5. Pestalotiopsis taxicola (CFCC59976) a culture on PDA b conidiomata formed on PDA c conidiogenous cells d-f conidia. Scale bars: 500 µm ( b ); 10 µm ( c-f ). Culture characteristics. Colonies on PDA reaching 90 mm diameter after seven days at 25 °C, with an undulate and radial edge, with dense aerial mycelium on surface, initially yellow in the centre, becoming white at the margin, with white appressed mycelia radiating outwards (Fig. 5a ). Conidiomata acervular in culture on PDA, globose, 200-700 μm in diameter, solitary or aggregated in clusters, exuding black conidial masses (Fig. 5b ). Material examined. China , Guangxi Province , from diseased needles of Chinese yew, May 2020 , Y. F. Wang (BJFC-S1954, holotype ); ex-type living culture CFCC59976, living cultures CFCC59978, CFCC59979 and CFCC59980 . Notes. Pestalotiopsis taxicola was phylogenetically placed in a clade encompassing P. unicolor , but as a unique lineage with high support (MP/ML = 100/100) (Fig. 2 ). Compared with P. unicolor (MFLUCC 12-0276, ex-type) and P. taxicola (CFCC59976, ex-type), there were one nucleotide difference in the ITS region and nine nucleotide differences in the tef-1α region. Morphologically, P. taxicola had smaller conidia (16.5-21 x 4-6 µm ) than P. unicolor (20-24.5 x 4-6 µm ). In addition, P. taxicola had only one basal appendage, whereas P. unicolor had 1-2 basal appendages ( Maharachchikumbura et al. 2012 ). Therefore, the four isolates were designated as a new species.