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Pyxidinopsis retiola

Pyxidiniopsis? retiolum Dodekova 1994

Holotype Dodekova 1994: pl. XII, fig. 1,
Locus typicus: borehole R-1 Junak, depth 1605 m, Northeastern Bulgaria.
Stratum typicum: Middle Tithonian, Chitinoidella Zone, Tica Fm.

Dimensions (in µm). Holotype: length: 117, breadth: 109. Range: length: 105-117, breadth: 98-109 (10 specimens measured).

Description: Dodekova 1994, p. 42-43
Proximate subspherical cyst with rounded antapical end and with a slight indication of an apical projection. The latter feature differs the new species from the original generic diagnosis. Most specimens show not evidence of this feature but there are some ones in suitable position that do. The autophragm, or appressed endophragm and periphragm, is thin, almost always deformed with secondary folds or broken. The ruptures are often in areas of the supposed cingulum and precingular plate series. The surface of the autophragm is fine reticulate or reticulo-vermiculate. The tabulation is indicated by archeopyle only. The archeopyle is precingular, type 1P (presumably 3"). Operculum free, in some rare cases it remains adherent in its anterior end. The significant feature of P? retiolum sp. n. is its large size, which is surprisingly constant.

Remarks. Pyxidiniopsis? retiolum sp. n. differs by other species of Pyxidinopsis by its great size and moderate ornamentation. P. challengerensis Habib, 1975 is smaller, with coarse reticulation. P. granulatum (Ioannides et al., 1976) is smaller too and granulate.

Occurrence. Boreholes: R-l Junak (depth 1605 m Middle Tithonian, Chitinoidella Zone, Tica Fm.); R-3 Junak (depth 1756 m, Early Tithonian, Tica Fm.); R-4 Junak (depth 1654 m, Early Tithonian, Tica Fm.).
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