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Heteraulacacysta everriculata
Heteraulacysta everriculata Islam, 1983
Holotype: Islam, 1983, pl.2, fig.9
Locus typicus: Isle of Sheppey, SE England
Stratum typicum: Early Eocene
Original diagnosis: Islam, 1983, p.237
Cyst ambitus subcircular in polar view but looks like a "curry dish with lid" in dorso-ventral views; proximochorate; biphragmal; endophragm is reticulate resulting from coalescence of densely distributed grana while a few discreie grana may still be present; periphragm psilate very thin and may be minutely punctate and folded along parasutures into crests delinea ting the paraplates; additional radial folds are commonly present in paracingular crests; paratabulation less distinct tban in other species of the genus particularly in dorso-ventrally disposed specimens which is 3", 6", xc, 6""", 1""""; paraplates 1p and 1ps were not observed; archeopyle is epicystal.
Dimensions: Holotype: cyst breadth 54 µm, dorso-ventral thickness 54 Ám, height of paracingular crests 12 µm. Range: cyst length 41-54 µm (2 specimens) , breadth 62(55)50 µm, dorso-ventral thickness 68(54)44 µm, height of paracingular crests 10-20 µm.
Affinities:
Islam, 1983, p.237: It differs from other species of the genus in possessing a reticulate endophragm and additional radial folds in paracingular crests.
Holotype: Islam, 1983, pl.2, fig.9
Locus typicus: Isle of Sheppey, SE England
Stratum typicum: Early Eocene
Original diagnosis: Islam, 1983, p.237
Cyst ambitus subcircular in polar view but looks like a "curry dish with lid" in dorso-ventral views; proximochorate; biphragmal; endophragm is reticulate resulting from coalescence of densely distributed grana while a few discreie grana may still be present; periphragm psilate very thin and may be minutely punctate and folded along parasutures into crests delinea ting the paraplates; additional radial folds are commonly present in paracingular crests; paratabulation less distinct tban in other species of the genus particularly in dorso-ventrally disposed specimens which is 3", 6", xc, 6""", 1""""; paraplates 1p and 1ps were not observed; archeopyle is epicystal.
Dimensions: Holotype: cyst breadth 54 µm, dorso-ventral thickness 54 Ám, height of paracingular crests 12 µm. Range: cyst length 41-54 µm (2 specimens) , breadth 62(55)50 µm, dorso-ventral thickness 68(54)44 µm, height of paracingular crests 10-20 µm.
Affinities:
Islam, 1983, p.237: It differs from other species of the genus in possessing a reticulate endophragm and additional radial folds in paracingular crests.