cells. The cell is spherical, about 8-15 um in diameter and uniformly covered in 20-40 spines. The spines are distinctly thickened at the base, and very narrow at the tips. The spines are organized in four whorls of 4, 8, 8, and 4 respectively. Cells contain a single nucleus and one parietal, cup-shaped chloroplast, which has a single, prominent pyrenoid with a starch sheath.

Asexual reproduction