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Heteraulacacysta granulata

Heteraulacysta granulata Jan du Chêne and Adediran, 1985

Holotype: Jan du Chêne and Adediran, 1985, pl.19, fig.8
Locus typicus: Benin-Ore Highway, Km 41, Nigeria
Stratum typicum: Late Paleocene-Early Eocene

Original diagnosis: Jan du Chêne and Adediran, 1985, p. 14
A species of Heteraulacacysta with an irregularly distributed granulate omamentation.

Original description: Jan du Chêne and Adediran, 1985, p. 14
Cyst proximochorate, subpolyhedral with an ovoidal outline in apical-antapical view. The endophragm and periphragm are closely appressed except where the periphragm forms parasutural folds which delineate a Gonyaulacacean type paratabulation (Bujak, 1980) as 1pr, 1"*, 3", 6", ?c, 6""", 1p, 1"""", 1ps. The shapes of the apical and preapical paraplates from the holotype are not completely detemminable. 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 altemation of four-sided paraplates (2""", 4""", 6""") and five-sided paraplates (3""" and 5"""). The posterior intercalary and the antapical paraplates are both small and pentagonal. The parasulcal paraplates have not been defined 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 ornamentation of the periphragm consists in regularly distributed granula.
Dimensions: Cyst body in apical-antapical view: 70-76x60-66 µm.

Affinities:
Jan du Chêne and Adediran, 1985, p. 14: This species is characterized by its smooth periphragm bearing irregularly spaced granulae. H. campanula Drugg andLoeblich 1967 shows a periphragm ornamented with grana and irregular spines that may fuse to from a very crude microreticulum and a very large (7µm) and radially striate cingular flanges (Drugg and Loeblich, 1967, p. 183).
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