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Cyclonephelium circulatum
Cyclonephelium circulatum He Chengquan, 1991
Holotype: He Chengquan, 1991, pl.10, fig.7
Age: Middle-Late Eocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description: Body round, usually lacking apical horn, and antapical horns are never seen. Cyst wall is thin, the surface has particles and a significant periphera ornamentation band determined by the processes; Processes rod-like, straight or curved, of varying lengths, 3.5-11μm, generally 7μm, ends simple, individual slightly tapering or slightly enlarged (but not bifurcated); The distribution of processes in the peripheral band may vary, usually more developed at the apex and antapex (with more and longer processes) and clustered, processes are few and short on both sides of the cyst, completely absent in the middle of dorsal and ventral surface. Archeopyle apical, (tA) type, the edge is the "Z" shape, with incision. Operculum preserved in situ or shed. Or with a yellow-green core. The total diameter is 75-95μm , the cyst diameter 66- 77.5μm (measured 6); the total diameter of the holotype 75μm, cyst diameter 66μm , The longest process 7μm.
Discussion: The new species is quite similar to Cyclonephelium distinctum in morphology, size and its basic structure. However, the former’s contour of dorsal-ventral side is round, apical horn is abenst (except on only one specimen), process short, ends simple or slightly expanded, no bifurcation, the processes distribution on the surrounding ornamentation band is uneven, developed at the apex and antapex and clustered; the latter often has an apical horn or an anapical horn, the processes are generally long, the ends of the majority are bifurcated, combined at in the base of the processes, the two are easy to distinguish. Accordingly, C. distinctum (Drugg, 1967, p.22, pl.3, fig.7), a specimen collected from the Danian stage e in California, USA, seems to belong to this new species.
Location and stratigraphy: Shache County Altashi, Wulagen fm, Wuqia County Basebulak, Basebulakfm member two, three.
Holotype: He Chengquan, 1991, pl.10, fig.7
Age: Middle-Late Eocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description: Body round, usually lacking apical horn, and antapical horns are never seen. Cyst wall is thin, the surface has particles and a significant periphera ornamentation band determined by the processes; Processes rod-like, straight or curved, of varying lengths, 3.5-11μm, generally 7μm, ends simple, individual slightly tapering or slightly enlarged (but not bifurcated); The distribution of processes in the peripheral band may vary, usually more developed at the apex and antapex (with more and longer processes) and clustered, processes are few and short on both sides of the cyst, completely absent in the middle of dorsal and ventral surface. Archeopyle apical, (tA) type, the edge is the "Z" shape, with incision. Operculum preserved in situ or shed. Or with a yellow-green core. The total diameter is 75-95μm , the cyst diameter 66- 77.5μm (measured 6); the total diameter of the holotype 75μm, cyst diameter 66μm , The longest process 7μm.
Discussion: The new species is quite similar to Cyclonephelium distinctum in morphology, size and its basic structure. However, the former’s contour of dorsal-ventral side is round, apical horn is abenst (except on only one specimen), process short, ends simple or slightly expanded, no bifurcation, the processes distribution on the surrounding ornamentation band is uneven, developed at the apex and antapex and clustered; the latter often has an apical horn or an anapical horn, the processes are generally long, the ends of the majority are bifurcated, combined at in the base of the processes, the two are easy to distinguish. Accordingly, C. distinctum (Drugg, 1967, p.22, pl.3, fig.7), a specimen collected from the Danian stage e in California, USA, seems to belong to this new species.
Location and stratigraphy: Shache County Altashi, Wulagen fm, Wuqia County Basebulak, Basebulakfm member two, three.