Plectodiscus Kozlova, 1972

Popova, Irina M., Baumgartner, Peter O., Guex, Jean, Tochilina, Svetlana V. & Glezer, Zoya I., 2002, Radiolarian biostratigraphy of Paleogene deposits of the Russian Platform (Voronesh Anticline), Geodiversitas 24 (1), pp. 7-59 : 46

Genus Plectodiscus Kozlova, 1972

Plectodiscus circularis ( Clark & Campbell, 1942) ( Fig. 7P )

Porodiscus circularis Clark & Campbell, 1942: 42 , pl. 11, figs 2, 6, 10.

Porodiscus uralicus – Lipman 1960: 86, pl. XI, figs 9-11. Xiphospira circularis – Sanfilippo & Riedel 1973: 526, pl. 14, figs 5-12, pl. 31, figs 4-7.

Plectodiscus circularis – Petrushevskaya & Kozlova 1972: 526, pl. 19, figs 9-12. — Blueford 1988: 250, pl. 5, figs 7, 8.

Circodiscus circularis – Kozlova 1999: pl. 9, fig. 2.

GEOGRAPHIC DISTRIBUTION. — California, Western Siberia, Gulf of Mexico, Atlantic Ocean, Russian Platform, southern part.

STRATIGRAPHIC RANGE. — Late Paleocene to middle Eocene ( Clark & Campbell 1942; Blueford & White 1984; Blueford 1988; Sanfilippo & Riedel 1973; Kozlova 1999); (?)late Paleocene-early Eocene (this study).

Figures

FIG. 7. — Early Eocene Radiolarian association, Petropavlovka Village, well 730, interval 44,3 m; A, B, Petalospyris sp. aff. argiscus Ehrenberg,1875; C, D, Petalospyris (?) sp.;E, F, Pterocodon ampla (Brandt,1936); G, Lychnocanoma bellum longipes (Kozlova,1966); H, Podocyrtis cf. papalis Ehrenberg, 1875; I, Lychnocanoma sp. aff. bandyca Mato & Theyer, 1980; J, Cycladophora cf. Pterocorys bicornis Popofsky, 1908; K, Lithostrobus picus (Ehrenberg,1875); L, Amphisphaera megaxyphos trixyphos (Clark & Campbell, 1942); M, Amphymenium splendiarmatum Clark & Campbell, 1942; N, Clathrocyclas ex. gr. universa Clark & Campbell, 1942; O, Prunopyle sp. aff. ovata Kozlova, 1966; P, Plectodiscus circularis (Clark & Campbell, 1942); Q, Petalospyris argiscus Ehrenberg, 1875; R, Anthocyrtidium sp. aff.pupa Clark & Campbell, 1942;S, Ommatogramma biconstrictus (Lipman,1953).Scale bars:100 µm.