Plagiopyxis oblonga  (Bonnet & Thomas, 1955) Bonnet & Thomas, 1960
= Plagiopyxis declivis var. oblonga  Bonnet & Thomas, 1955

Diagnosis: In lateral view, the test is oval in shape and greyish in color, or brownish due to the presence of an underlying chitinous membrane. Shell covered with quartz plates, irregular, bound by a brownish cement, exuding at the bonds. Pseudostome placed very high in the narrow part of the oval entirely concealed by the dorsal part curved into a visor; detectable by adjusting the focus, this visor protrudes quite a bit. In lateral view, the ventral side plunges gently towards the interior of the test at a less open angle: this side is covered at its stopping point by the return of the dorsal side coming to meet it, passing far enough from it, so as to spare the opening of the pseudostome.

Dimensions: Length 75-92 µm; width 49-64 µm; dorso-ventral (height) 37-43 µm.

Ecology: Soil. France.