So far I have only found Xanthidium antilopaeum var. ornatum in the Paradieswiesen (Austria) and in the Simmelried. In the Simmelried, however, the species occurs only very rarely.

Each semi-cell of Xanthidium antilopaeum has 4 pairs of straight or slightly curved spines. The equatorial spines are usually bent towards the center of the cell (s. fig. 1 a). In the center of each half cell there is an ornamentation of round or elongated warts, which can be very variable. In the specimens of my population it was a ring of round tubercles on a brownish colored field (s. fig. 2).

Xanthidium antilopaeum var. ornatum can easily be distinguished from the similar species Xanthidium cristatum and Xanthidium fasciculatum by the number of spines per semi-cell. While Xanthidium antilopaeum var. ornatum has 8 spines per half cell (4 pairs), the other two species have 10 spines (4 pairs and 2 solitary spines each).