Cyclonephelium formosum (Iosifova, 1992, p.61, pl.9, figs.3a-c; text-figs.1c-d) Fauconnier in Fauconnier and Masure, 2004, p.146. Holotype: Iosifova, 1992, pl.9, figs.3a-c; text-figs.1c-d; Iosifova, 1996, pl.16, figs.6a-b; text-figs.5A-B. Originally Circulodinium, subsequently (and now) Cyclonephelium. Age: Valanginian.

Description: Iosifova, 1992, p. 75
(fig.1c, d). Cyst is proximate, subspherical, dorsoventrally flattened. Two (one) small antapical horns are sometimes present. Wall is bilaminar; autophragm and periphragm are very close together. Periphragm forms processes, which are developed only on periphery of cyst. Middle parts of ventral and dorsal sides are free of such processes. Closer toward center, processes decrease greatly in size. Processes are continuous, closed, buccinate, oblate, more rarely digitate, cylindrical of bifucate, and comprise about 1/5 width of cyst. Some processes joined in twos and threes at proximal or distal ends of membrane. Bases of processes are often perforated. Archeopyle is apical, tA, with zig-zag margin. There are no signs of paratabulation apart from structure of archeopyle.

Dimensions in microns (without apex):
Spec. No.LWD
Holotype (4831/4196-1)99.894.119.2
4831/4196-2-17382.517.3
4831/4196-2-280.680.621.1
4831/4196-3-376.880.615.3

Comparison. Differs from C. distinctum (Deflandre et Cookson) Jansonius in perforate bases of processes and also in that some processes may be linked together at distal or proximal ends of membrane.

Distribution. Valanginian of Moscow syneclise.