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Fromea chinensis
Fromea chinensis He Chengquan, 1991
This species was not validly published in He Chengquan and Wang Kede, 1990.
Holotype: He Chengquan, 1991, pl.6, fig.12
Age: Middle Eocene
Description in He Chengquan, 1991 translated by Suning Hou, 07-01-2019
Description Body elongated, waist slightly wider, divided into nearly trapezoidal two parts by an equatorial suture. The upper cyst is slightly smaller than the lower cyst, antapex part is wide and round; Some specimens are constricted in the anterior part of the upper cyst, forming a distinct "shoulder". Thin wall, single layer, surface with faint particles and longitudinal ridges; ridges are long, can extend from the upper cyst to the lower cyst, usually straight on the upper cyst, bendable on the lower cyst, with ridge width of about 1 μm and about 5 μm from each other. Cyst outline nearly smooth or microwave-like. The equatorial zone of the body always has a "crack" or cingulum, which is a reflection of the cingulum. Archeopyle apical, large, the edge is corniform (archeopyle suture zigzag, angular), formed by the loss of apical plates, operculum free. Cyst length (without top) 55-75μm, width 48-50 μm, (measured 3), holotype length (top missing) 70μm, width 50μm, the archeopyle width 20μm.
Comparison: This new species is obviously distinguishable from other species in this genus by its cyst shape, ornamental characteristics of the wall surface, and the character of its cingulum.
Location and stratigraphy: Ulugquat county Basebulak, Wulagen fm.
This species was not validly published in He Chengquan and Wang Kede, 1990.
Holotype: He Chengquan, 1991, pl.6, fig.12
Age: Middle Eocene
Description in He Chengquan, 1991 translated by Suning Hou, 07-01-2019
Description Body elongated, waist slightly wider, divided into nearly trapezoidal two parts by an equatorial suture. The upper cyst is slightly smaller than the lower cyst, antapex part is wide and round; Some specimens are constricted in the anterior part of the upper cyst, forming a distinct "shoulder". Thin wall, single layer, surface with faint particles and longitudinal ridges; ridges are long, can extend from the upper cyst to the lower cyst, usually straight on the upper cyst, bendable on the lower cyst, with ridge width of about 1 μm and about 5 μm from each other. Cyst outline nearly smooth or microwave-like. The equatorial zone of the body always has a "crack" or cingulum, which is a reflection of the cingulum. Archeopyle apical, large, the edge is corniform (archeopyle suture zigzag, angular), formed by the loss of apical plates, operculum free. Cyst length (without top) 55-75μm, width 48-50 μm, (measured 3), holotype length (top missing) 70μm, width 50μm, the archeopyle width 20μm.
Comparison: This new species is obviously distinguishable from other species in this genus by its cyst shape, ornamental characteristics of the wall surface, and the character of its cingulum.
Location and stratigraphy: Ulugquat county Basebulak, Wulagen fm.