Periphaena pentasteriscus ( Clark & Campbell, 1942 )

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 : 43-45

Periphaena pentasteriscus ( Clark & Campbell, 1942) ( Fig. 17I, J )

Heliodiscus pentasteriscus Clark & Campbell, 1942: 39 , pl. 3, fig. 8. — Petrushevskaya & Kozlova 1972: 523, pl. 13, figs 6, 7.

GEOGRAPHIC DISTRIBUTION. — Atlantic Ocean, California, Voronesh Anticline.

STRATIGRAPHIC RANGE. — Middle to latest middle Eocene ( Clark & Campbell 1942; Blueford & White 1984); Eocene ( Petrushevskaya & Kozlova 1972); middle to late Eocene (this study).

Periphaena perplexus ( Clark & Campbell, 1942) ( Fig. 10A, B )

Heliodiscus perplexus Clark & Campbell, 1942: 40 , pl. 3, fig. 12.

Trochodiscus hoplites Lipman, 1953: 141 , pl. XII, fig. 7.

Heliodiscus lentis Lipman, 1960: 83 , pl. XI, figs 5, 6; pl. XIV, figs 1, 2. — Kozlova 1984: 205, pl. 10, fig. 10; 1990: pl. XI, fig. 12.

Astrophacus testatus Kozlova in Kozlova & Gorbovets 1966: 73, pl. XI, fig. 7.

Heliodiscus inca – Kozlova 1999: 222, pl. 17, fig. 14; pl. 21, fig. 8; pl. 24, fig. 2 (only).

GEOGRAPHIC DISTRIBUTION. — California, Northern and Western Siberia, eastern slope of the Ural Mountains, Russian Platform, southern part.

STRATIGRAPHIC RANGE. — Middle to latest middle Eocene ( Clark & Campbell 1942; Blueford & White 1984); early Eocene ( Lipman 1953, 1960; Kozlova & Gorbovets 1966; Kozlova 1990); (?)late Paleoceneearly Eocene to late Eocene (this study).

REMARKS

It is very difficult to see the difference between Heliodiscus perplexus and Heliodiscus lentis Lipman, 1960 (p. 83, pl. XI, figs 5, 6; pl. XIV, figs 1, 2), as the thickness of spines might be a result of a dissolution and because of that it can not be considered as the feature for a new species definition. To our point of view all above mentioned species are synonyms.

H. inca sensu Kozlova (1999) is a group of species, in a major quantity of images, different to H. inca holotype by: 1) the number and shape of main spines – for example, pl. 17, fig. 14 and pl. 21, fig. 8, the specimen has 10 or more round main spines, instead of nine angular, described by Clark & Campbell; and 2) by the surface porosity – for example, pl. 40, fig. 9, specimen has an irregular size and distribution of pores, and a round main spines.

Periphaena quadrata ( Clark & Campbell, 1942) ( Fig. 16B, C )

Heliodiscus quadratus Clark & Campbell, 1942: 38 , pl. 3, fig. 16. — Kozlova 1990: pl. XI, fig. 2.

Astrophacus tetradialis – Tochilina 1966: 285, pl. 2, fig. 2a, b.

Heliodiscus hexasteriscus – Kozlova 1990: pl. XI, fig. 3. GEOGRAPHIC DISTRIBUTION. — California, Voronesh Anticline.

STRATIGRAPHIC RANGE. — Middle Eocene ( Clark & Campbell 1942; Kozlova 1990); middle to late Eocene (this study).

Figures

FIG. 17. — Early and middle-late Eocene Radiolarians from different localities; A, Druppatractus polycentrus Clark & Campbell, 1942, o/p 294/4, interval 6.3 m; B, Ellipsostylus anisoxyphos Clark & Campbell, 1942, o/p 294/6, interval 8.3 m; C, Hexacontium pachydermum Jørgensen, 1900, well 510C, interval 44.0 m; D, Heterosestrum formosum trispinum (Tochilina, 1972) emend., well 730C, interval 43.7 m; E, Lithomelissa sp. aff. ehrenbergi Bütschli, 1882, well 510C, interval 40.0 m; F, Euscenarium (?) sp., well 730C, interval 44.3 m; G, Theocorys anapographa Riedel & Sanfilippo, 1970, o/p 294/3, interval 5.3 m; H, Periphaena decora Ehrenberg, 1873, well 730C, interval 43.7 m; I, J, Periphaena pentasteriscus (Clark & Campbell, 1942), well 510C, interval 40.0 m; K, Tripocyrtis (?) sp., o/p 294/11, interval 12.8 m; L, Porodiscus charlestonensis Clark & Campbell, 1945, well 510C, interval 44.0 m; M, S, Spongodiscus ex. gr. cruciferus (Clark & Campbell, 1942), well 730C, interval 43.7 m; N, Lithomelissa sp. aff. spongiosa Bütschli, 1882, o/p 294/4, interval 6.3 m; O, Ommatogramma sp. aff. biconstrictus (Lipman, 1953), well 730C, interval 38.8 m; P, Q, Peripyramis magnifica magnifica (Clark & Campbell, 1942), well 730C, interval 43.7 m; R, Prunobrachium (?) sp., well 730C, interval 43.7 m. Scale bar: 100 µm.

FIG. 10. — Early Eocene Radiolarian association, Petropavlovka Village, Well 730, interval 44.3 m; A, B, Periphaena perplexus (Clark & Campbell, 1942); C, F, J, Haliomma (?) faceta (Krasheninnikov, 1960); D, G, Heterosestrum formosum (Tochilina, 1970); E, Periphaena sp. aff. Heliodiscus inca (Clark & Campbell, 1942); H, K, Stylotrochus festivus Clark & Campbell, 1942; I, Heterosestrum (?) sp.; L, M, Amphicraspedium praemurrayanum Kozlova, 1999; N, Ommatogramma biconstrictus (Lipman, 1953). Scale bars: 100 µm.

FIG. 16. — Early and middle-late Eocene Radiolarians from different localities; A, F, Amphisphaera gonioxyphos (Clark & Campbell, 1942), o/p 294/11, interval 12.8 m; B, C, Periphaena quadrata (Clark & Campbell, 1942), well 510C, interval 36.0 m; D, Amphisphaera megaxyphos tetraxyphos (Clark & Campbell, 1942), o/p 294/4, interval 6.3 m; E, Carposphaera globosa Clark & Campbell, 1945, well 510C, interval 36.0 m; G, Dorylonchidium fructiforme Clark & Campbell, 1942, o/p 294/10, interval 12.2 m; H, I, Conoactinomma sp. aff. Conosphaera stilloformis Lipman, 1960, well 510C, interval 36.0 m; J, Calocyclas sp. aff. barbadensis Ehrenberg, 1875, well 730C, interval 43.7 m; K, L, Anthocyrtium sp., well 730C, interval 38.8 m; M, Theocotyle venezuelensis Riedel & Sanfilippo, 1970, o/p 294/11, interval 12.8 m; N-P, Tripodiscinus kaptarenkoae (Gorbunov, 1979), o/p 294/10, interval 12.2 m; Q, Calocyclas undella (Clark & Campbell, 1942), o/p 294/2, interval 4.3 m; R, Callimitra sp. aff. Tripilidium clavipes Clark & Campbell, 1945, o/p 294/6, interval 8.3 m; S, Tripodiscinus sp., well 730C, interval 38,8 m; T, Ceratocyrtis rhabdophora rhabdophora (Clark & Campbell, 1945), o/p 294/5, interval 7.3 m; U, Botryostrobus sp., well 730C, interval 38.8 m; V, Callimitra cf. atavia Goll, 1979, o/p 294/6, interval 8.3 m. Scale bars: 100 µm.