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Ascostomocystis gigantea
Ascostomocystis giganteus, Singh, 1983
Holotype: Singh, 1983, pl.45, fig.1
Locus typicus: Upper Shaftesbury Formation of the Peace River area
Stratum typicum: Early Cenomanian
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Original description: [Singh, 1983, p. 129-130]:
Description:
Proximate, cavate cysts; body dorsoventrally flattened, flask-shaped, and with an apical archeopyle at the narrower, anterior end;
archeopyle elliptical, 36 to 50 µm wide;
endophragm dark, finely granular, about 2 µm thick, and forming a thick rim around the apical archeopyle; periphragm membranous, wrinkled, adhering to the endophragm dorsally, ventrally and around the archeopyle rim; periphragm bag-like and free around the circumference; paracingulum represented by low, parallel, transverse, equatorial ridges on the periphragm;
parasulcus and paratabulation not indicated.
Dimensions:
Size range: Length of the pericyst 180(182)184 µm. Holotype 184 µm. Breadth of the pericyst 170(174)178 µm. Holotype 178 µm. Length of the endocyst 140(156)172 µm. Holotype 172 µm. Breadth of the endocyst 118(132)146 µm. Holotype 146 µm. Specimens measured 3.
Affinities:
Ascostomocystis giganteus differs from Ascostomocystis maxima Singh, 1971, in being larger, having wider space between the endophragm and periphragm around the circumference, and lacking the longitudinal ridges which partially outline the paratabulation on the periphragm.
Holotype: Singh, 1983, pl.45, fig.1
Locus typicus: Upper Shaftesbury Formation of the Peace River area
Stratum typicum: Early Cenomanian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Singh, 1983, p. 129-130]:
Description:
Proximate, cavate cysts; body dorsoventrally flattened, flask-shaped, and with an apical archeopyle at the narrower, anterior end;
archeopyle elliptical, 36 to 50 µm wide;
endophragm dark, finely granular, about 2 µm thick, and forming a thick rim around the apical archeopyle; periphragm membranous, wrinkled, adhering to the endophragm dorsally, ventrally and around the archeopyle rim; periphragm bag-like and free around the circumference; paracingulum represented by low, parallel, transverse, equatorial ridges on the periphragm;
parasulcus and paratabulation not indicated.
Dimensions:
Size range: Length of the pericyst 180(182)184 µm. Holotype 184 µm. Breadth of the pericyst 170(174)178 µm. Holotype 178 µm. Length of the endocyst 140(156)172 µm. Holotype 172 µm. Breadth of the endocyst 118(132)146 µm. Holotype 146 µm. Specimens measured 3.
Affinities:
Ascostomocystis giganteus differs from Ascostomocystis maxima Singh, 1971, in being larger, having wider space between the endophragm and periphragm around the circumference, and lacking the longitudinal ridges which partially outline the paratabulation on the periphragm.