Phenacoscorpius scorpionfishes have very bony heads armed with strong spines and without an occipital pit on the top of the head behind the eyes. The suborbital ridge has 5-6 spines. There are teeth on the sides of the roof of the mouth but none in the front. The uppermost preopercular spine is the largest. There are 12 spines and 9 soft rays in the
dorsal fin and 3 spines and 5 soft rays in the
anal fin. The
pectoral fins have 15-17 rays with the upper rays being branched, the central rays being the longest and the lower rays having their tips exposed. The lateral line is incomplete being made up of only 4-5 pored scales at the front. These scorpionfishes vary in size from a standard length of in
P. longirostris and a total length of in
P. megalops. ==Distribution and habitat==