Spore size without ornamentation. Spines were without interconecting ridges as far as I could tell. Perideum 1 mm thick (measurement only from one specimen).
Ornamentation (0.8) 0.9 – 1.5 (1.7) µm N = 12 Me = 1.3 µm
Thanks Doug. Yes, the spores seem to fit with verrucosum as described by FoS, vol 2 p384 under the entry for S.areolatum.
“the most reliable differentiating feature is the size of the spores, which in S. verrucosum are 8-11.6 mm with spines 1-1.4 mm long (GROSS et al. 1980)”
Macroscopically the outer surface of the perideum was quite smooth (without scales) which is a bit inconvenient. However, from the images I can find online it seems quite variable in appearance. I also read somewhere that it can shed its scales as it matures.
I stumbled across another couple of earthballs this week. Both have reticulated spores with bovista having a more complete network (easier to see than to photograph). Bovista also has a thinner perideum.