 The spore print is olive-brown to pale cinnamon-brown. Individual spores are thin-walled, hyaline (translucent), and smooth. Their shape is ellipsoid to roughly cylindrical in face view or inequilateral when viewed in profile, and they measure 9.5 – 10 by 2.8 – 3.5 μm. The basidia (spore-bearing cells of the hymenium) are hyaline, club-shaped and four-spored, with dimensions of 33 – 36 by 8 – 10 μm. The thin-walled cystidia are rare to scattered on the tube surface but abundant on the pores, where they usually occur in massive clusters. They appear dark brown when mounted in a dilute (3 %) solution of potassium hydroxide (KOH), and are cylindric to roughly club-shaped, measuring 43 – 79 by 7 – 10 μm. They are usually encrusted with pigment, although some may be hyaline. The tissue comprising the tube is hyaline, and made of divergent to nearly parallel hyphae that are 3 – 5 μm wide. The pileipellis is a tissue type known as an ixotrichodermium (made of interwoven gelatinized hyphae); it stains brown in KOH, and is made of hyphae that are 4 – 5 μm wide. The stipe cuticle is made of clusters of cystidia similar to those found in the hymenium. Clamp connections are absent in the hyphae of S. pungens.
