Spicules spindle-shaped with tapering ends, 0.3-0.6 mm long (almost 2.5 times shorter than in Acanthochiasma rubescens), stiff. Cell body bulky, with numerous sensitive axopodia radiating in all directions. Endoplasm consisting of central black-reddish sphere surrounded by clear vesicular sheet including most nuclei. Ectoplasm resembling transparent jelly striated by anastomosed cytoplasmic strands and axopodial axonemes. As in Acanthochiasma rubescens, periplasmic cortex more visible when cell is completely inflated after long period of calm. Gametogenesis occurs in oblong cyst limited by very thin birefringent plates. Remnants of spicules forming bundle in cyst center. Myonemes extremely thin, appearing in EM as narrow flat bands.