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Meiourogonyaulax dicrypta
Meiourogonyaulax dicrypta Gitmez and Sarjeant, 1972
NOW Escharisphaeridia. Originally Meiourogonyaulax, subsequently Lithodinia, thirdly Meiourogonyaulax?, fourthly Canningia?, fifthly (and now) Escharisphaeridia. Questionable assignment: Below (1981a, p.31).
Holotype: Gitmez and Sarjeant, 1972, pl.7, fig.6; text-fig.22.
Age: Early-Late Kimmeridgian.
Original diagnosis: Gitmez and Sarjeant, 1972, p.225
Cyst subspherical to spherical, with the tabulation 4", 6"", 6c, 7""", 1p, 1"""", poorly marked by low ridges. Cingulum more or less equatorial and circular. Sulcus deep, short, confined to the hypotract, broadening towards the antapex. Cyst wall thick and composed of two layers: thick endophragm and thin pcriphragm. The periphragm bulges out on the apex to form a blunt apical horn, a cavity being developed between the two layers. Surface of the cyst is densely granular. Apical archaeopyle always present; sometimes the operculum remains attached to the shell, ventrally.
Dimensions: Holotype: length (apex lacking) 40 µm, breadth 52 µm. Range: overall length 70-90 µm, breadth 52-88 µm, length (apex lacking) 40-64 µm. Measured specimcns 8 in number.
Original description: Gitmez and Sarjeant, 1972, p.226
The spherical to subspherical cyst is divided into two equal parts by the moderately narrow cingulum. Both epitract and hypotract are dome-shaped; the epitract bears a small, blunt, hollow apical horn. Four apical and Six precingular plates make up the epitract: plate 1" is elongate, the other apical plates are broader. Plates 1" and 6" are somewhat reduced and plates 2"" and 5" are the largest of the precingular plates. Seven postcingular plates are present on the hypotract. Plates 1""" and 2""" are reduced because of the presence of a large intercalary plate (1p). Plates 3""", 4""" and 6""" are relatively large; plate 7""" is reduced. The single antapical plate (1"""") is quite large and convex. The cingulum is poorly indicated, formed by six plates of variable size. The sulcus is deep and, in its posterior portion, very wide. An apical archaeopyle forms by loss of the apical plates.
NOW Escharisphaeridia. Originally Meiourogonyaulax, subsequently Lithodinia, thirdly Meiourogonyaulax?, fourthly Canningia?, fifthly (and now) Escharisphaeridia. Questionable assignment: Below (1981a, p.31).
Holotype: Gitmez and Sarjeant, 1972, pl.7, fig.6; text-fig.22.
Age: Early-Late Kimmeridgian.
Original diagnosis: Gitmez and Sarjeant, 1972, p.225
Cyst subspherical to spherical, with the tabulation 4", 6"", 6c, 7""", 1p, 1"""", poorly marked by low ridges. Cingulum more or less equatorial and circular. Sulcus deep, short, confined to the hypotract, broadening towards the antapex. Cyst wall thick and composed of two layers: thick endophragm and thin pcriphragm. The periphragm bulges out on the apex to form a blunt apical horn, a cavity being developed between the two layers. Surface of the cyst is densely granular. Apical archaeopyle always present; sometimes the operculum remains attached to the shell, ventrally.
Dimensions: Holotype: length (apex lacking) 40 µm, breadth 52 µm. Range: overall length 70-90 µm, breadth 52-88 µm, length (apex lacking) 40-64 µm. Measured specimcns 8 in number.
Original description: Gitmez and Sarjeant, 1972, p.226
The spherical to subspherical cyst is divided into two equal parts by the moderately narrow cingulum. Both epitract and hypotract are dome-shaped; the epitract bears a small, blunt, hollow apical horn. Four apical and Six precingular plates make up the epitract: plate 1" is elongate, the other apical plates are broader. Plates 1" and 6" are somewhat reduced and plates 2"" and 5" are the largest of the precingular plates. Seven postcingular plates are present on the hypotract. Plates 1""" and 2""" are reduced because of the presence of a large intercalary plate (1p). Plates 3""", 4""" and 6""" are relatively large; plate 7""" is reduced. The single antapical plate (1"""") is quite large and convex. The cingulum is poorly indicated, formed by six plates of variable size. The sulcus is deep and, in its posterior portion, very wide. An apical archaeopyle forms by loss of the apical plates.