Pseudofoenus fallax is a large (12-16mm), reddish-brown species variously marked with black, and with metasomal segments paler laterally at the hind borders. The mesonotum surface is rugose and lacking punctures. As with all Tasmanian Pseuodofoenus species, females can be identified by the 14-segmented antennae, and males by the 13-segmented antennae.
Pseudofoenus cf. fallax (male)