A Gram-staining positive facultative anaerobic, non-motile strain, sk1b4T, was isolated from canker of symptomatic bark tissue of a Populus × euramericana. 16S rRNA gene sequence analyses showed that strain sk1b4T shared the highest similarity with Arcanobacterium phocisimile (94.1%). Within the phylogenetic tree, the novel isolate formed a distinct branch from Actinobaculum, Arcanobacterium, and Trueperella. The percentage of conserved proteins calculated from genomic sequence indicated a low level of relatedness between the novel strain and its phylogenetic neighbors. Growth of the novel strain occurred at temperatures between 10 and 41°C, and within a pH range of 6.0-9.0; optimal growth occurred at 30°C and at pH 6.0-9.0. Growth also occurred within a NaCl concentration of 1%-5% (w/v). The major fatty acids of the strain were C14:0, C16:0, and C18:1ω9c and major polar lipids were glycolipid, phosphatidylinositol mannoside, phospholipid, diphosphatidylglycerol, and phosphatidylglycerol. Respiratory quinone was absent. On the basis of phenotypic and genotypic characteristics, we propose that the novel isolate should be classified as a novel species in a new genus: Ancrocorticia populi gen. nov., sp. nov. The type strain is sk1b4T (=CFCC 14564T=KCTC 39919T).