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Pseudomuderongia asymmetrica
Muderongia asymmetrica (Brideaux, 1977) Jain and Khowaja-Ateequzzaman, 1984; Emendation: Monteil, 1991b, p.472, as Muderongia asymmetrica.
Now Muderongia. Originally (and now) Muderongia, subsequently Pseudomuderongia. This species was retained in Muderongia Cookson and Eisenack, 1958, by Stover and Williams, 1987
Holotype: Brideaux, 1977, pl.15, figs.9-10; pl. 16, fig. 1
Locus typicus: Richardson Mountains, Mackenzie, Canada
Stratum typicum: Aptian-Albian
Original diagnosis: Brideaux, 1977, p. 40
Shape: Pericyst ambitus elongate, the main portion pentagonal to subrhombic; epipericyst prolonged into a long, tapering apical horn; hypopericyst prolonged antapically to form a longer tapering left antapical horn and a shorter, tapering to acuminate right antapical horn; laterally, hypopericyst produced to form a shorter right postcingular and longer left postcingular horn. Left antapical horn from one and one-half to three times the length of the right antapical horn; right postcingular horn distinctly longer and up to four times as long as the left postcingular horn; right postcingular horn broad at the base but tapering abruptly at about half its length.
Endocyst ambitus follows that of pericyst, but extends only slightly or not at all into the apical, postcingular and antapical horns. One apical, two lateral and two antapical pericoels formed in the broad sense; ambital pericoel not developed; dorso-ventral compression .
Phragma: Periphragm about 1.0 µm thick, of constant thickness; surface smooth or granulate. Endophragm thin, less than 0.5 µm thick, of constant thickness.
Paratabulation: Evident only in the formation of the archeopyle, denoted by the zig-zag shape of the archeopyle outline-details of paratabulation not observed.
Archeopyle/operculum: Peri- and endoarcheopyle formed by the loss of the apical part of the peri- and endocyst; perioperculum presumably simple, detached, as is endoperculum; detached opercula not observed. Formula. A/A.
Pericingulum/perisulcus. Not observed.
Dimensions: Pericyst width (2 complete specimens), 103, 118 µm; pericyst width (excluding postcingular horns), 43-58 µm; left postcingular horn, 12-38 µm; right postcingular horn, 15-33 µm; left antapical horn, 25-60 µm; right antapical horn, 10-35 µm.
Now Muderongia. Originally (and now) Muderongia, subsequently Pseudomuderongia. This species was retained in Muderongia Cookson and Eisenack, 1958, by Stover and Williams, 1987
Holotype: Brideaux, 1977, pl.15, figs.9-10; pl. 16, fig. 1
Locus typicus: Richardson Mountains, Mackenzie, Canada
Stratum typicum: Aptian-Albian
Original diagnosis: Brideaux, 1977, p. 40
Shape: Pericyst ambitus elongate, the main portion pentagonal to subrhombic; epipericyst prolonged into a long, tapering apical horn; hypopericyst prolonged antapically to form a longer tapering left antapical horn and a shorter, tapering to acuminate right antapical horn; laterally, hypopericyst produced to form a shorter right postcingular and longer left postcingular horn. Left antapical horn from one and one-half to three times the length of the right antapical horn; right postcingular horn distinctly longer and up to four times as long as the left postcingular horn; right postcingular horn broad at the base but tapering abruptly at about half its length.
Endocyst ambitus follows that of pericyst, but extends only slightly or not at all into the apical, postcingular and antapical horns. One apical, two lateral and two antapical pericoels formed in the broad sense; ambital pericoel not developed; dorso-ventral compression .
Phragma: Periphragm about 1.0 µm thick, of constant thickness; surface smooth or granulate. Endophragm thin, less than 0.5 µm thick, of constant thickness.
Paratabulation: Evident only in the formation of the archeopyle, denoted by the zig-zag shape of the archeopyle outline-details of paratabulation not observed.
Archeopyle/operculum: Peri- and endoarcheopyle formed by the loss of the apical part of the peri- and endocyst; perioperculum presumably simple, detached, as is endoperculum; detached opercula not observed. Formula. A/A.
Pericingulum/perisulcus. Not observed.
Dimensions: Pericyst width (2 complete specimens), 103, 118 µm; pericyst width (excluding postcingular horns), 43-58 µm; left postcingular horn, 12-38 µm; right postcingular horn, 15-33 µm; left antapical horn, 25-60 µm; right antapical horn, 10-35 µm.