The lichen has a thin, yellowish-green to greenishthallus that is tightly attached to its bark. It has black, apothecia that are 1–5 mm long and 0.3–0.4 mm wide. The is wedge-shaped at its apex, and is. The is brownish and measures 8–15 μm high. Its asci are cylindrical and two-spored, measuring 90–110 by 13–25 μm. Its ascospores are oblong to ellipsoid in shape, and dimensions of 35–45 by 110–155 μm. No lichen products were detected in Platygramme lueckingii. Platygramme hainanensis is similar in morphology and appearance, but this lichen does not have two-spored asci.