Quadrulella acuminata Van Oye, 1958
Diagnosis: Test rather pyriform with a stretched base with converging sides, very slightly concave at the top. Pseudostome bordered by a very little pronounced and almost straight chitinoid edge. Square plates with here and there a rectangular; these latter are, however, few in number. The plates do not overlap, but are juxtaposed without leaving gaps, not even at the corners. The plates of the posterior tip are not square, but elongated and triangular.
Q. acuminata differs from all other species in this genus by its posterior part ending in a point.
As for its dimensions, it could be classified under the species Q. symmetrica but this one has the base largely rounded.
Dimensions: Length 102 µm; width 60 µm; thickness 13 µm; L/W 1.7.
Ecology: Sphagnum at 3000 m., Congo, Africa.