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Leptodinium ambiguiformis

Leptodinium? ambuigiformis Dodekova 1994

Holotype Dodekova 1994: pl. XII, fig.s. 9-11
Locus typicus: Borehole R-7 Sultanci, depth 1765 m, Northeastern Bulgaria.
Stratum typicum: Late Tithonian, Crassicollaria Zone, Tica Fm.

Dodekova 1994, p. 39-40:
The species is presented by numerous specimens but not even one is enough significant to be a holotype. The specimens are deformed or broken, or do not manifest all specific feature because of their position in the slide. The proposed holotype is also cracked but illustrated passably the diagnostic specific features.

Dimensions (in Ám). Holotype: length: 113, breadth: 96. Range: length: 100-113, breadth: 94-100 (11 specimens measured).

Description: Dodekova 1994, p. 39-40:
Proximate cyst, subspherical to ovoidal, with rounded antapex and weakly expressed apical bulge. Acavate. The autophragm is ornamented with characteristic superficial irregular reticulum. The tabulation is gonyaulacacean indicated by very low ridges, entire, rare fine-denticulate. Tabulation formula: 1-2?pr, 4", la-2a?, 6", 6c, 6"", lp, lpv, 1"", Os (Fig. 6). The cingulum is proportionally narrow, helicoidal, disposed at the widest part of the cyst. The sulcus is short, straight and wide, undivided (1pv only). The plate 1pv is large, lies immediately below a little rectangular plate 1"" and plate 6c. The plate 1" is long, narrow at its posterior end slightly widen to the apex. The plate 4" is rectangular, larger than the five-sided plate 6"". The configuration of the tabulation pattern is demonstrated on Fig. 5. The problematic is existence of plates 2pr and 1a because the meshes of the superficial reticulum may coincide with dimensions of these plates. Archeopyle precingular, type lP (3")

Remarks. Dodekova 1994, p. 39-40:
As is apparent by the specific name the new species L? ambiguiformis is silnilar to L? ambiguum (Deflandre, 1939) but the latter is nearly twice smaller than the former. It possess more prominent apical protrusion, narrowed and longer plate 6", alveolar to granular ornamentation, without anterior intercalaries. L? ambigulformis sp. n. is similar and may be conspecific with Leptodinium? sp. B from Upper Tithonian rocks in New Zealand (Helby et al., 1988, p. 148, fig. 19, H).

Occurrence. Borehole R-7 Sultanci (depth 1765 m, Tica Fm., Late Tithonian, Crassicollaria Zone).
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