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Odontochitina grandis
From Fensome et al., 2019:
Odontochitina grandis Fedorova-Shakhmundes, 1980, p.6, pl.1, fig.3. Holotype: Fedorova-Shakhmundes, 1980, pl.1, fig.3. Age: Cenomanian.
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Original description: [Fedorova-Shakhmundes, 1980, p.6] (translated from Russian):
Odontochitina grandis, Theodorova-Shakhmundes, sp. n.
Table 1. Fig. 3
Odontochitina operculatum (O. We) Deflandre: 1967, Vozzhennikova [20]. p. 156-157, pl. LXXX, figs. 1-5, pl. LXXXI, figs. 1-3.
Holotype - No. 6887/1-11, 21, VNIGRI, Leningrad; Caspian Lowland, Krykkuduk, borehole 5-K "bis", depth 915.7-924.4 m; Upper Cretaceous, Cenomanian.
Material. 6 specimens in good preservation.
Description. Theca is large in size, in the dorsal-ventral (?) projections of irregularly elliptical outlines with an internal body with long apical and two antapical horns. In the fossil state, as a rule, isolated parts of the theca are found. The apical part is small, conical in shape, rm, the internal body is rounded, conical or teardrop-shaped. The apical horn is long, tubular, gradually tapering toward the distal end. The antapical part is large; the internal body is rounded in outline, in some specimens with two projections at the base of the horns. The antapical horns are long, unequal in size, straight or curved, connected at the bases, sometimes significantly below the border of the internal body. One horn is tubular, of approximately the same diameter along its entire length, the other has a wide base, exceeding the diameter of the first by 3-3.5 times, then sharply tapering and continuing as a narrow tubular outgrowth, gradually tapering toward the end, like the first. The theca membrane is dense, smooth, and two-layered. The color is light yellow.
Dimensions, µm. Apical part: L 150-350 (175.0); apical horn: L 150-305 (150.0); D at the base 18-35 (18.3); D at the distal end 2.7-3.3 (3.3); antapical part: L 200-250 (200.0); D 54-81 (70.0); antapical horns 100-200 (100.0), 80-150 (80.0); D of the bases 10 and 33.
Comparison. Differs from Odontochitina operculata (O. We.). Deflandre [158, 159] by the larger size of the theca, the thickness of the membrane, and the pronounced asymmetry of the apical and antapical horns.
Location and stratigraphic setting. Kaliningrad region. Lower Cretaceous, Albian. Caspian lowland, Dnieper-Donets interfluve. Upper Cretaceous, Cenomanian. Smolensk region. Upper Cretaceous.
Odontochitina grandis Fedorova-Shakhmundes, 1980, p.6, pl.1, fig.3. Holotype: Fedorova-Shakhmundes, 1980, pl.1, fig.3. Age: Cenomanian.
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Original description: [Fedorova-Shakhmundes, 1980, p.6] (translated from Russian):
Odontochitina grandis, Theodorova-Shakhmundes, sp. n.
Table 1. Fig. 3
Odontochitina operculatum (O. We) Deflandre: 1967, Vozzhennikova [20]. p. 156-157, pl. LXXX, figs. 1-5, pl. LXXXI, figs. 1-3.
Holotype - No. 6887/1-11, 21, VNIGRI, Leningrad; Caspian Lowland, Krykkuduk, borehole 5-K "bis", depth 915.7-924.4 m; Upper Cretaceous, Cenomanian.
Material. 6 specimens in good preservation.
Description. Theca is large in size, in the dorsal-ventral (?) projections of irregularly elliptical outlines with an internal body with long apical and two antapical horns. In the fossil state, as a rule, isolated parts of the theca are found. The apical part is small, conical in shape, rm, the internal body is rounded, conical or teardrop-shaped. The apical horn is long, tubular, gradually tapering toward the distal end. The antapical part is large; the internal body is rounded in outline, in some specimens with two projections at the base of the horns. The antapical horns are long, unequal in size, straight or curved, connected at the bases, sometimes significantly below the border of the internal body. One horn is tubular, of approximately the same diameter along its entire length, the other has a wide base, exceeding the diameter of the first by 3-3.5 times, then sharply tapering and continuing as a narrow tubular outgrowth, gradually tapering toward the end, like the first. The theca membrane is dense, smooth, and two-layered. The color is light yellow.
Dimensions, µm. Apical part: L 150-350 (175.0); apical horn: L 150-305 (150.0); D at the base 18-35 (18.3); D at the distal end 2.7-3.3 (3.3); antapical part: L 200-250 (200.0); D 54-81 (70.0); antapical horns 100-200 (100.0), 80-150 (80.0); D of the bases 10 and 33.
Comparison. Differs from Odontochitina operculata (O. We.). Deflandre [158, 159] by the larger size of the theca, the thickness of the membrane, and the pronounced asymmetry of the apical and antapical horns.
Location and stratigraphic setting. Kaliningrad region. Lower Cretaceous, Albian. Caspian lowland, Dnieper-Donets interfluve. Upper Cretaceous, Cenomanian. Smolensk region. Upper Cretaceous.