Test large, subcylindrical, elongate, septa in-tensely and regularly folded, forming cuniculi: wall thin, protheca may be differentiated in places, outer whorls with weakly developed diaphanotheca and inner tectorium, small chomata in earliest whorls only, well-developed axial deposits fill the central area from the proloculus to the poles. U. Carboniferous (U. Moscovian); USSR: Donets Basin, central Asia.