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Deflandrea arcuata
Deflandrea arcuata Vozzhennikova, 1967; emend. Lentin and Vozzhennikova, 1990
Holotype: Vozzhennikova, 1967, pl. 68, figs. 3a-b; Lentin and Vozzhennikova, 1990, pl.6, figs.6-8, text-fig.23
Locus typicus: Yantarnoe, Kaliningrad region, Russia
Stratum typicum: Late Eocene-Early Oligocene
Translation Vozzhennikova 1967: Lees in Sarjeant (Ed.), 1971
Original description: Vozzhennikova, 1967, p. 143-144
Description: Theca elongate oval with uniformly thickened lateral walls and ovoid internal body. Epitheca larger than hypotheca with and arciform outline and a small blunt apical process (horn). Hypotheca trapeziform with straight lateral walls. Antapical margin slightly concave with its margins forming two slight rounded outgrowths which represent the antapical horns. Transverse furrow shallow, equatorial and noticeable on the lateral walls of the theca but not on the dorsal and ventral walls. Longitudinal furrow bearly discernable. Surface of theca smooth, coloured; internal body finely punctate. Pylome trapeziform or elliptical.
Emended description: Lentin and Vozzhennikova, 1990, p.50
Cyst outline ovally peridinioid with a short apical horn and a roundly convex pericingular region; antapex with two more or less equal, very reduced antapical horns, with the left antapical horn sometimes more developed; endocyst oval in outline, dividing the cyst equally, or displaced slightly towards the apex; circumcavate. Periphragm smooth to minutely granulose; endophragm densely covered in small baculae, approximately 2Ám in height. Paratabulation indicated by archeopyle and paracingulum, peridinioid. The periarcheopyle is broad hexa (latideltaform), operculum free; the endoarcheopyle is also broad hexa or undeveloped. The paracingulum is indicated only by slight indentations at the lateral margins. Parasulcus indicated by a very slight depression on the hypocyst.
Size: Holotype, length 119 Ám, width 86 Ám, width of paracingulum about 8 Ám; endocyst, length 64 Ám, width 70 Ám. Range, length 108 - 119 Ám, width 75 - 86 Ám, width of paracingulum 8 Ám; endocyst, length 64 - 68 Ám, width 65 - 70 Ám.
Affinities:
Vozzhennikova, 1967, p. 144: This species differs from others in the genus in having an arciform epitheca and an internal body which is ovoid. The horns are also very feebly developed. The species bears some similarity to Deflandrea cf. heterophlycta Defl. et. Cooks. described by Alberti (1959, pl. 8, fig. 7) from the Lower Eocene of Germany. It differs however from the latter in having less strongly developed apical and antapical horns, in the sculpturing to the theca and the internal body and also in size.
Holotype: Vozzhennikova, 1967, pl. 68, figs. 3a-b; Lentin and Vozzhennikova, 1990, pl.6, figs.6-8, text-fig.23
Locus typicus: Yantarnoe, Kaliningrad region, Russia
Stratum typicum: Late Eocene-Early Oligocene
Translation Vozzhennikova 1967: Lees in Sarjeant (Ed.), 1971
Original description: Vozzhennikova, 1967, p. 143-144
Description: Theca elongate oval with uniformly thickened lateral walls and ovoid internal body. Epitheca larger than hypotheca with and arciform outline and a small blunt apical process (horn). Hypotheca trapeziform with straight lateral walls. Antapical margin slightly concave with its margins forming two slight rounded outgrowths which represent the antapical horns. Transverse furrow shallow, equatorial and noticeable on the lateral walls of the theca but not on the dorsal and ventral walls. Longitudinal furrow bearly discernable. Surface of theca smooth, coloured; internal body finely punctate. Pylome trapeziform or elliptical.
Emended description: Lentin and Vozzhennikova, 1990, p.50
Cyst outline ovally peridinioid with a short apical horn and a roundly convex pericingular region; antapex with two more or less equal, very reduced antapical horns, with the left antapical horn sometimes more developed; endocyst oval in outline, dividing the cyst equally, or displaced slightly towards the apex; circumcavate. Periphragm smooth to minutely granulose; endophragm densely covered in small baculae, approximately 2Ám in height. Paratabulation indicated by archeopyle and paracingulum, peridinioid. The periarcheopyle is broad hexa (latideltaform), operculum free; the endoarcheopyle is also broad hexa or undeveloped. The paracingulum is indicated only by slight indentations at the lateral margins. Parasulcus indicated by a very slight depression on the hypocyst.
Size: Holotype, length 119 Ám, width 86 Ám, width of paracingulum about 8 Ám; endocyst, length 64 Ám, width 70 Ám. Range, length 108 - 119 Ám, width 75 - 86 Ám, width of paracingulum 8 Ám; endocyst, length 64 - 68 Ám, width 65 - 70 Ám.
Affinities:
Vozzhennikova, 1967, p. 144: This species differs from others in the genus in having an arciform epitheca and an internal body which is ovoid. The horns are also very feebly developed. The species bears some similarity to Deflandrea cf. heterophlycta Defl. et. Cooks. described by Alberti (1959, pl. 8, fig. 7) from the Lower Eocene of Germany. It differs however from the latter in having less strongly developed apical and antapical horns, in the sculpturing to the theca and the internal body and also in size.