The morphological ontogeny of Melanozetes interruptus Willmann, 1953 is redescribed and illustrated. The juveniles of this species are brown with dark-brown sclerites. In juveniles humeral organ and humeral macrosclerite are present, seta c1 is inserted on humeral macrosclerite, and setae c2 and c3 are inserted on microsclerites. In the larva, the gastronotal shield has seven pairs of setae (d-, l-series and h1), in the nymphs it has nine pairs (d-, l-, h-series), whereas all setae of p-series are inserted on microsclerites, which is unique in Melanozetes Hull, 1916. In most nymphs of this genus seta p1 is inserted on gastronotal shield. In the juveniles and adult the legs are stocky, all femora are flattened, and femora I and II have a large ventral carina. Solenidion ω2 on tarsus I is located anterior to solenidion ω1 and is longer than ω1. In this species tarsal setae a are clearly longer than seta s.