Zatrachys serratus (Cope 1878; Early Permian) is related to Eoscopus in the LRT. Adults had elaborate bony spikes on the skull. Note the large medial fontanelle between the nares. It may have housed an inflatable sac.

Eoscopus lockardi (Daly 1994; Late Carboniferous) was originally considered a sister to Micropholis, but here nests with Zatrachys. Both share a large medial fontanelle and small nares located laterally. The posterior skull includes several quadratojugal and tabular spines. The skull is enormous relative to the body.