Argynnia spicata (Wailes, 1913) comb. nov.
Basionym: Nebela spicata, Wailes, 1913

Diagnosis: Shell ovoid, moderately compressed, formed of various-sized oval or irregularly shaped scales; fundus circular, furnished with a single row of 6-8 hollow spines; shell in lateral view pyriform; transverse section elliptical, ratio of axes about 5 : 3; aperture broadly elliptical with undulate margin bordered by a row of oval scales; plasma normal; pseudopodia not observed.

Dimensions: Length (without horns) 120-140 µm; breadth 100-125 µm; aperture 32-40 µm; thickness 0.5 to 0.6 of the width; length of horns 20-30 µm.

Habitat: Freshwater. Sphagnum. Sandia, Peru.

Remarks: Wailes, 1913: “In the small quantity of material available some ten individuals were found, but owing to the fragile nature of the horns many of these were imperfect. The test is opaque, strongly constructed, and of a robust form, the outlines follow regular curves, being free from excrescences; the crenulations around the aperture are often pronounced, resembling those of A. dentistoma, a species to which it bears a close likeness when deprived of the spines. It is distinguished from Argynnia caudata, a species found in association with it, by its much larger size and robust form, its more regular outlines and greater number of spines.”