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Heteraulacacysta pustulata
Heteraulacacysta pustulata Jan du Chêne and Adediran, 1985
Holotype: Jan du Chêne and Adediran, 1985, pl.19, fig.1
Locus typicus: Benin-Ore Highway, Km 41, Nigeria.
Stratum typicum: Late Palaeocene-Early Eocene
Original diagnosis: Jan du Chêne and Adediran, 1985, p. 15
A species of Heteraulacacysta with a pustulate omamentation.
Original description: Jan du Chêne and Adediran, 1985, p. 15
Cysts proximochorate, subpolyhedral with an ovoidal to circular outline in apical-antapical view. The endophragm and periphragm are each very thin. The periphragm forms parasutural folds defining a Gonyaulacacean type paratabulation of 1pr, 4", 6", ?c, 6""", 1p, 1"""", 1ps which also corresponds to the Bujak definition (1980, p. 58) of the Heteraulacacysta paratabulation of 1pr, 1"*, 3", 6", ?c, 6""", 1p?, 1"""", 1ps. Paraplates 1", 3" and 5" are typically five-sided, and 2", 4" and 6" are four-sided. The paratabulation of the hypocyst shows, exclusif of the first postcingular, an alternation of five-sided paraplates (3""", 5""") and four-sided paraplates (2""", 4""", 6"""). The posterior intercalary and the antapical paraplates are both small and pentagonal. The sulcal paraplates have not been observed yet. The paracingulum is limited by two parallel crests interrupted by a well defined parasulcal furrow. The archeopyle is epicystal, type [tAtP]; the archeopyle suture lies within the paracingulum. The position of the parasulcus is indicated by a slight indentation of the paracingulum seen best in apical-antapical view. The oramentation of the periphragm is pustulate, pustulae being regularly spaced on the intratabular areas of the cyst paraplates.
Dimensions: Holotype: 80x80 Ám (lateral view). Range: 65-84x58-80 Ám (apical view). Pustulae: up to 2 Ám in diameter. Number of specimens measured: 12.
Affinities:
Jan du Chêne and Adediran, 1985, p. 15: This species is easy to distinguish with its typical pustalate ornamentation.
Holotype: Jan du Chêne and Adediran, 1985, pl.19, fig.1
Locus typicus: Benin-Ore Highway, Km 41, Nigeria.
Stratum typicum: Late Palaeocene-Early Eocene
Original diagnosis: Jan du Chêne and Adediran, 1985, p. 15
A species of Heteraulacacysta with a pustulate omamentation.
Original description: Jan du Chêne and Adediran, 1985, p. 15
Cysts proximochorate, subpolyhedral with an ovoidal to circular outline in apical-antapical view. The endophragm and periphragm are each very thin. The periphragm forms parasutural folds defining a Gonyaulacacean type paratabulation of 1pr, 4", 6", ?c, 6""", 1p, 1"""", 1ps which also corresponds to the Bujak definition (1980, p. 58) of the Heteraulacacysta paratabulation of 1pr, 1"*, 3", 6", ?c, 6""", 1p?, 1"""", 1ps. Paraplates 1", 3" and 5" are typically five-sided, and 2", 4" and 6" are four-sided. The paratabulation of the hypocyst shows, exclusif of the first postcingular, an alternation of five-sided paraplates (3""", 5""") and four-sided paraplates (2""", 4""", 6"""). The posterior intercalary and the antapical paraplates are both small and pentagonal. The sulcal paraplates have not been observed yet. The paracingulum is limited by two parallel crests interrupted by a well defined parasulcal furrow. The archeopyle is epicystal, type [tAtP]; the archeopyle suture lies within the paracingulum. The position of the parasulcus is indicated by a slight indentation of the paracingulum seen best in apical-antapical view. The oramentation of the periphragm is pustulate, pustulae being regularly spaced on the intratabular areas of the cyst paraplates.
Dimensions: Holotype: 80x80 Ám (lateral view). Range: 65-84x58-80 Ám (apical view). Pustulae: up to 2 Ám in diameter. Number of specimens measured: 12.
Affinities:
Jan du Chêne and Adediran, 1985, p. 15: This species is easy to distinguish with its typical pustalate ornamentation.