Thalassocalyce inconstans exhibits a bell-shaped body resembling that of a medusa, with a diameter reaching up to 15 cm. The body is transparent, colorless, and often challenging to detect. Short comb rows, whitish in color, characterize its structure. The mouth is located at the apex of a central conical peduncle, and a pair of small tentacles hangs from the sides of the peduncle, each adorned with lateral filaments.