Protoplagiopyxis delamarei Bonnet, 1962

Diagnosis: Shell dark brown, elliptical in dorsal view, extended forward by a fairly well individualized visor, but forming an integral part of the rumen. In lateral view, the shell is strongly swollen in the dorso-posterior region and the dorso-ventral distance then drops quite abruptly in the region of the visor. Very clear ventral sole, without depression or slope of any kind. Narrow and elongated pseudostome, drawing an arc of a circle of about 35°; its width does not exceed 8 um. Ventral lip very slightly folded towards the dorsal face. Exogenous covering, quartzose, incorporating in addition some very tenuous dark particles giving the whole a finely chamois appearance.

Dimensions: Length 100 µm, width 85 µm, maximum dorso-ventral distance 45 to 50 µm, dorso-ventral distance at the level of the dorsal lip of the pseudostome 25 µm, pseudostome 45 x 8 µm.

Habitat: Soil.