Trinema nassa  Decloitre, 1965

Diagnosis: Shell just as other Trinema species with similar arrangement of the plates, but the inner border of the pseudostome is ornamented with small plates each with a short spine that points to the center of the aperture. Spines about 1.5 µm long. Shell compressed.

Dimensions: Decloitre (1965): Shell length 50—55 µm; width 25—30 µm; aperture 10—12 µm.

Habitat: Freshwater.

Geographical distribution: Congo, Mbila, Africa.