Body oval. Carapace always with rounded posterior end, lacking spine; varying in shape from elongate-oval to hemispherical (Pseudevadne tergestina, female; Pseudevadne tergestina, male). Elevator muscles of antenna diverging dorsally.
Exopods of thoracic limbs l-4 with 2,3,3,1 setae, respectively (Pseudevadne tergestina, exopods).
Females with several rows of hypodermal cells present in brood pouch (often disappearing in preserved specimens).
Resting eggs: spherical, 0.19-0.24 mm (mean 0.20 mm) in diameter, egg membrane smooth (but SEM observation shows fine mat of microvillar structures), with clear perimeter, cytoplasm thickly granulated, light-brownish.
Total length female (standard length): 0.3-1.3 mm (0.3-0.9 mm).
Total length male: 0.5-0.8 mm (0.3-0.6 mm).