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Cryptarchaeodinium longispinum
Cryptarchaeodinium longispinum He Chengquan, 1991
Holotype: He Chengquan, 1991, pl.21, fig.13; text-fig.13
Age: Early Eocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description: cyst nearly circular or oval, upper and lower cyst nearly equal, no apical antapical horns. Wall thickness about 2μm, two layers, thin outer wall, surface dense granular; Inner wall thick, smooth surface. The plates are marked with thin sutural ridge as the boundary; the ridge is low, with long thin processes; the number and length of the processes variable, length 2-12.5μm (but most are around 12.5μm), solid, distally with "Y" -shaped bifurcation; On the holotype, the processes are only found on the sutural ridges of the cingulum and the lower cyst, some protrusions may be damaged; The tabulation is approximately 4', 6", 6c, 6"’, 1"". The lower cyst plates are clearer than the upper cyst, of which the a piece of the postcingular plates (1 '’') is small, outline nearly triangular. The cingulum is at the equatorial position, apparently left-handed spiral, width 7μm; Cingulum plates are well developed.The sulcus seems to be limited to the lower cyst, and its width equals to the cingulum, but no plate displayed. Archeopyle is unknown, the apex of the holotype has fallen off, but not sure whether it is an apical archeopyle or mechanical damage, It is unclear whether the precingular plate 3 "or 3" - 4 " is lost. Cyst length (excluding processes) is greater than 45μm, width 45--66μm (measured 4); Holotype longer than 57.5μm, width 65μm, processes length 5-12.5μm, cingulum width 7μm. Discussion: The number of the apical plates is inferred, but the tabulation type is undoubtedly consistent with its genus. Due to the long processes on the sutural ridges, the cyst is proximochorate. The new species differs from the type species in the long processes on the sutural ridge, distally "Y" -shaped bifurcation etc.
Location and stratigraphy: Wuqia County Basebulak; Qimugen fm at the bottom of the upper member.
Holotype: He Chengquan, 1991, pl.21, fig.13; text-fig.13
Age: Early Eocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description: cyst nearly circular or oval, upper and lower cyst nearly equal, no apical antapical horns. Wall thickness about 2μm, two layers, thin outer wall, surface dense granular; Inner wall thick, smooth surface. The plates are marked with thin sutural ridge as the boundary; the ridge is low, with long thin processes; the number and length of the processes variable, length 2-12.5μm (but most are around 12.5μm), solid, distally with "Y" -shaped bifurcation; On the holotype, the processes are only found on the sutural ridges of the cingulum and the lower cyst, some protrusions may be damaged; The tabulation is approximately 4', 6", 6c, 6"’, 1"". The lower cyst plates are clearer than the upper cyst, of which the a piece of the postcingular plates (1 '’') is small, outline nearly triangular. The cingulum is at the equatorial position, apparently left-handed spiral, width 7μm; Cingulum plates are well developed.The sulcus seems to be limited to the lower cyst, and its width equals to the cingulum, but no plate displayed. Archeopyle is unknown, the apex of the holotype has fallen off, but not sure whether it is an apical archeopyle or mechanical damage, It is unclear whether the precingular plate 3 "or 3" - 4 " is lost. Cyst length (excluding processes) is greater than 45μm, width 45--66μm (measured 4); Holotype longer than 57.5μm, width 65μm, processes length 5-12.5μm, cingulum width 7μm. Discussion: The number of the apical plates is inferred, but the tabulation type is undoubtedly consistent with its genus. Due to the long processes on the sutural ridges, the cyst is proximochorate. The new species differs from the type species in the long processes on the sutural ridge, distally "Y" -shaped bifurcation etc.
Location and stratigraphy: Wuqia County Basebulak; Qimugen fm at the bottom of the upper member.