With a body comprising a head, a torso, two legs, two arms, and five-fingered hands, the Melitto were humanoids. Nevertheless, the segmented plates of chitin visible on their heads and hairy forearms betrayed their insectile nature. The Melitto face was covered in four plates, the largest being at the top, but did not feature visible eyes or mouth.

However, they did have auditory organs, and the small bristles lining their body were in fact specialized, feathery cilia that could sense vibrations and detect electrical fields. Additionally, those cilia gave the Melitto a keen sense of smell. Their extraordinary scent-memories not only helped them navigate just as well as if they had eyes, but also gave them extensive identification and tracking skills.

When operating in atmospheres different from their own, the Melitto wore breathing tubes and carried dispensers filled with sugary nutrient fluid.

The species had at least two sexes: male and female. One known individual, a male named Sarco Plank, stood 1.82 meters tall. The Melitto language consisted of humming sounds produced by their facial plates. To communicate with other species, they wore vocoders that translated their hums into an understandable voice.

Melitto were eusocial beings who lived in hives ruled by queens and their adolescent female servants—called myrmitrices—who in turn controlled their own stables of male workers—or myrmites—who gathered food, built the physical hive structure, and battled other hives as soldier-myrmites. Whenever a hive’s population increased too much for it to operate at full efficiency, it became necessary to found a new hive. The myrmitrices then started fighting each other with the help of their warrior followers. When a victor emerged, she gained the right to be queen of a new hive. The myrmites who had the misfortune of surviving their myrmitrix’s defeat were cast away from their hive, becoming ronin. Most ronin left their homeworld to become expert hunters and thieves. Some, however, were rumored to found their own queenless communities in the subterranean caves of their planet, such as the Hive Ronin.