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Charlesdowniea wulagenensis
Charlesdowniea wulagenensis, (Mao Shaozhi and Norris, 1988), Lentin and Williams, 1993
Originally Kisselevia, subsequently Charlesdowniea, thirdly (and now) Talladinium.
Holotype: Mao and Norris, 1988, pl.13, fig.6
Locus typicus: Tarim Basin, Xinjiang Province, China
Stratum typicum: Wulagen Formation, Wuluokeqiate section, upper Eocene
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Original description as Kisselovia wulagenensis: [Mao and Norris, 1988, p.50]:
Diagnosis:
Cyst proximochorate, circumcavate. Ambitus rounded-rhombic to rounded-pentagonal, with slightly prominent apex and two poorly developed antapical horns. Periphragm bearing penitabular processes connected distally by trabeculae and encircled penitabularly by thin membranes to form simulate complexes. Endoblast large, almost filling the whole pericoel.
Tabulation typically peridinioid, indicated by the penitabular process complex; 4", 3a, 7", XC, 5""", 2"""".
Archeopyle intercalary, type (I)a, quadra 2a style; operculum attached anteriorly.
Description:
Epitract triangular, almost equal to the triangular-trapezoid hypotract. Antapical horns reduced to shallow lobes or small triangles.
Periphragm smooth; endophragm smooth to granulate.
Processes simple and solid, capitate or bifurcate distally, 3 to 7 µm long and 0.5 to 1 µm across, arranged penitabularly in one row in each complex, connected distally by trabeculae, encircled and connected by very thin membranes to form complete complexes simulating the plate. Sporadic intratabular processes also possibly occurring. Solid trabeculae possibly transforming gradually and proximally into thin and transparent membranes seen on the profile. Not clear whether the membranes covering or not covering the top of the fenced areas. The small apical and antapical pericoels are connected by 1 to 2µm wide ambital pericoel related to the large subspherical to rounded-rhombic endoblast.
Sulcus restricted to the hypotract.
Dimensions:
Length 85 to 105 µm (holotype 90 µm), width 67 to 103 µm (holotype 76 µm); 15 specimens measured.
Affinities:
Kisselovia wulagenensis differs from K. (?) clathrata (Eisenack, 1938) and K. coleothrypta (Williams and Downie, 1966), in having one row of penitabular processes united distally by trabeculae and encircled by membranes; the other two species have numerous intratabular processes connected distally by a perforate membrane.
Originally Kisselevia, subsequently Charlesdowniea, thirdly (and now) Talladinium.
Holotype: Mao and Norris, 1988, pl.13, fig.6
Locus typicus: Tarim Basin, Xinjiang Province, China
Stratum typicum: Wulagen Formation, Wuluokeqiate section, upper Eocene
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Kisselovia wulagenensis: [Mao and Norris, 1988, p.50]:
Diagnosis:
Cyst proximochorate, circumcavate. Ambitus rounded-rhombic to rounded-pentagonal, with slightly prominent apex and two poorly developed antapical horns. Periphragm bearing penitabular processes connected distally by trabeculae and encircled penitabularly by thin membranes to form simulate complexes. Endoblast large, almost filling the whole pericoel.
Tabulation typically peridinioid, indicated by the penitabular process complex; 4", 3a, 7", XC, 5""", 2"""".
Archeopyle intercalary, type (I)a, quadra 2a style; operculum attached anteriorly.
Description:
Epitract triangular, almost equal to the triangular-trapezoid hypotract. Antapical horns reduced to shallow lobes or small triangles.
Periphragm smooth; endophragm smooth to granulate.
Processes simple and solid, capitate or bifurcate distally, 3 to 7 µm long and 0.5 to 1 µm across, arranged penitabularly in one row in each complex, connected distally by trabeculae, encircled and connected by very thin membranes to form complete complexes simulating the plate. Sporadic intratabular processes also possibly occurring. Solid trabeculae possibly transforming gradually and proximally into thin and transparent membranes seen on the profile. Not clear whether the membranes covering or not covering the top of the fenced areas. The small apical and antapical pericoels are connected by 1 to 2µm wide ambital pericoel related to the large subspherical to rounded-rhombic endoblast.
Sulcus restricted to the hypotract.
Dimensions:
Length 85 to 105 µm (holotype 90 µm), width 67 to 103 µm (holotype 76 µm); 15 specimens measured.
Affinities:
Kisselovia wulagenensis differs from K. (?) clathrata (Eisenack, 1938) and K. coleothrypta (Williams and Downie, 1966), in having one row of penitabular processes united distally by trabeculae and encircled by membranes; the other two species have numerous intratabular processes connected distally by a perforate membrane.