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Deflandrea musculopsis
Deflandrea musculopsis Mao Shaozhi and Norris, 1988
Holotype: Mao Shaozhi and Norris, 1988, pl.10, fig.8
Locus typicus: Wulagen Formation, Qimugen section, China
Stratum typicum: Late Paleocene-Early Oligocene
Original diagnosis: Mao Shaozhi and Norris, 1988, p. 43-44
Cyst proximate, circumcavate to cornucavate, small in size (less than 70 Ám). Ambitus rounded, pentagonal, with apical horn and two small antapical horns.
Endoblast spherical to subspherical, relatively large, occupying major portion of pericoel. Wall thin and smooth. Archeopyle intercalary, type (I), broad hexa 2a; transverse AI 0.6 to 0.7 (holotype 0.63). Operculum free.
Original description: Mao Shaozhi and Norris, 1988, p. 44
Cyst small, length usually less than 60 Ám. Apical horn blunt or rounded, usually with broad base, 6 to 11 Ám long, 6 to 18 Ám wide at base. Two antapical horns small (2 to 5 Ám long, 3 to 6 Ám wide at their bases), equal or slightly unequal, with left one bigger. Periphragm smooth or finely granulate; endophragm smooth, thin, with many longitudinal folds. Ambital pericoel very narrow (0 to 2.5 Ám wide) because of relatively large spherical to subspherical endoblast filling large portion of pericoel. Cingulum 4 to 6 Ám wide, delimited by folds or low ridges, planar or slightly levorotatory. Indications of tabulation other than archeopyle and cingulum absent. Omphalos often found near junction of cingulum and sulcus, spherical to subspherical in shape, readily stained, darker colour than adjacent wall. Dimensions: Length 45 to 67.5 Ám (holotype 57 Ám), width 31 to 54 Ám (holotype 41 m); 45 specimens measured (see Text-Fig. 14).
Affinities:
Mao Shaozhi and Norris, 1988, p. 44: On the basis of its small size (usually less than 60 Ám) and its thin and almost smooth wall, this species can be distinguished from all other species of Deflandrea, with the exception of D. psilata, which has a circumcavate cyst with oval endoblast and broad ambital pericoel, and a standard hexa (I) archeopyle. D. musculopsis is closely comparable to Senegalinium microgranulatum and Subtilisphaera ventriosa. It differs from Senegalinium microgranulatum in the combination of the following features: (I) the wall is smooth rather than granulate; (2) the ambital pericoel is always weakly developed instead of absent; (3) the archeopyle is broad hexa style rather than standard hexa style. Subtilisphaera ventriosa has no indication of an archeopyle. D. musculopsis is also similar to Phelodinium pumilum; however, the latter species has a very thin and transparent periphragm and an intercalary archeopyle 2a typically with the antapical margin close to the cingulum.
Holotype: Mao Shaozhi and Norris, 1988, pl.10, fig.8
Locus typicus: Wulagen Formation, Qimugen section, China
Stratum typicum: Late Paleocene-Early Oligocene
Original diagnosis: Mao Shaozhi and Norris, 1988, p. 43-44
Cyst proximate, circumcavate to cornucavate, small in size (less than 70 Ám). Ambitus rounded, pentagonal, with apical horn and two small antapical horns.
Endoblast spherical to subspherical, relatively large, occupying major portion of pericoel. Wall thin and smooth. Archeopyle intercalary, type (I), broad hexa 2a; transverse AI 0.6 to 0.7 (holotype 0.63). Operculum free.
Original description: Mao Shaozhi and Norris, 1988, p. 44
Cyst small, length usually less than 60 Ám. Apical horn blunt or rounded, usually with broad base, 6 to 11 Ám long, 6 to 18 Ám wide at base. Two antapical horns small (2 to 5 Ám long, 3 to 6 Ám wide at their bases), equal or slightly unequal, with left one bigger. Periphragm smooth or finely granulate; endophragm smooth, thin, with many longitudinal folds. Ambital pericoel very narrow (0 to 2.5 Ám wide) because of relatively large spherical to subspherical endoblast filling large portion of pericoel. Cingulum 4 to 6 Ám wide, delimited by folds or low ridges, planar or slightly levorotatory. Indications of tabulation other than archeopyle and cingulum absent. Omphalos often found near junction of cingulum and sulcus, spherical to subspherical in shape, readily stained, darker colour than adjacent wall. Dimensions: Length 45 to 67.5 Ám (holotype 57 Ám), width 31 to 54 Ám (holotype 41 m); 45 specimens measured (see Text-Fig. 14).
Affinities:
Mao Shaozhi and Norris, 1988, p. 44: On the basis of its small size (usually less than 60 Ám) and its thin and almost smooth wall, this species can be distinguished from all other species of Deflandrea, with the exception of D. psilata, which has a circumcavate cyst with oval endoblast and broad ambital pericoel, and a standard hexa (I) archeopyle. D. musculopsis is closely comparable to Senegalinium microgranulatum and Subtilisphaera ventriosa. It differs from Senegalinium microgranulatum in the combination of the following features: (I) the wall is smooth rather than granulate; (2) the ambital pericoel is always weakly developed instead of absent; (3) the archeopyle is broad hexa style rather than standard hexa style. Subtilisphaera ventriosa has no indication of an archeopyle. D. musculopsis is also similar to Phelodinium pumilum; however, the latter species has a very thin and transparent periphragm and an intercalary archeopyle 2a typically with the antapical margin close to the cingulum.