The history of the early descriptions of Prosopistoma is reviewed, and the steps taken to trace the original material described as Prosopistoma variegatum Latreille, 1833 are outlined. Eaton (1884) designated P. variegatum as the ‘‘type’’ of the genus Prosopistoma. Because only the larva was described by Latreille (1833) and this material is no longer available, a larva of this species was selected as the neotype. Scanning electron micrographs of some of the key larval characters provide additional detail for morphological characters not previously described in the Prosopistomatidae. The associated adult male and subimaginal male and female collected from the same sites as verified larvae of P. variegatum are described for the first time.