Macroscopically indistinguishable from Glutinoglossum glutinosum, but with ascospores that vary between 3- and 7-septate, and are 4- or 5-septate when mature. In G. glutinosum they are consistently 3-septate. According to Fedoseva et al. (2017) the extra septa appear at a late stage of development and within intact asci the extra septa are often not present; in the material examined from Yorkshire this feature was not consistently observed. According to Arauzo (in litt.) some populations of G. glutinosum may also have ascospores with more than three septa, so sequencing is needed for a robust identification.