Diaphanosoma is characterized by a compound eye located at the center of its head and long second antennae with two branches. Its body is entirely covered by a carapace, and numerous setae are arranged in rows along the large second antennae. The most distinctive feature of Diaphanosoma is its elongated second antennae, which can extend beyond the body and often protrude to the side when preserved. They also have rounded heads and lack a crest on their head. The second antennae can reach the posterior margin of the carapace. Females of Diaphanosoma typically grow between 0.8 mm and 1.2 mm in length.