Lunaspis were flattened fish with short trunk and long, curved cornual plates. These long, spine-like plates give the suggestion of a crescent moon, hence the generic name. The nostrils and the anterior part of the headshield around the orbits, is covered by a number of tiny scales, as is the long trunk.
There are three known species in the genus Lunaspis:
- Lunaspis broili
- Lunaspis heroldi
- Lunaspis pruemiensis