Theocyrtis litos ( Clark & Campbell, 1945 )

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 : 50

Theocyrtis litos ( Clark & Campbell, 1945) ( Fig. 14F )

Calocyclas litos Clark & Campbell, 1945: 44 , pl. 6, fig. 13.

GEOGRAPHIC DISTRIBUTION. — California, Voronesh Anticline.

STRATIGRAPHIC RANGE. — Middle to late Eocene ( Clark & Campbell 1945; Blueford & White 1984; Blueford 1988); late Eocene (this study).

REMARKS

The specimen named Albatrossidium litos (see Kozlova 1999: pl. 35, fig. 3) can not be attributed to species named Theocyrtis litos , because of the difference in: 1) shape of the third segment – the holotype has no trend to reduce conicaly the diameter of its operture; and 2) in porosity – the diameter of pores of the third segment is much larger than in the holotype.

Figures

FIG. 14. — A-I, Early and middle Eocene Radiolaria; A, Desmospyris anthocyrtoides (Bütschli, 1882), o/p 1, interval 35.5-39.3 m; B, Desmospyris sp. aff. anthocyrtoides Bütschli, 1882, o/p 1, interval 35.5-39.3 m; C, D, Thecosphaera magnaporulosa (Clark & Campbell, 1942), Well 510C, interval 40.0 m; E, Trypansosphaera sp. aff. Conosphaera abstrusa Moksyakova, 1970, o/p 294/7, interval 9.3 m; F, Theocyrtis litos (Clark & Campbell, 1945), o/p 294/2, interval 4.2 m; G, Theocyrtis scolopax (Ehrenberg, 1875), o/p 294/1, interval 3.2 m; H, Tholospyris acuminata Hertwig, 1879, o/p 294/6, interval 8.3 m; I, Tripodiscium sp., o/p 294/7, interval 9.3 m; J-T, middle-early late Eocene Radiolarian association from Sergeevka Village, o/p 1, interval 35.5-39.3m; J, Phormocyrtis sp. aff. embolum (Ehrenberg, 1873); K, Calocyclas extensa contracta Clark & Campbell, 1942; L, Druppatractus trichopterus Clark & Campbell, 1942; M, Pterocodon lex Sanfilippo & Riedel, 1979; N, Q, Ceratocyrtis stigi (Bjørklund, 1976); O, Amphisphaera megaxyphos megaxyphos (Clark & Campbell, 1942); P, Porodiscus sp.; R, S, Thecosphaera californica Clark & Campbell, 1942; T, Ceratocyrtis charlestonensis (Clark & Campbell, 1945). Scale bars: A, B, J-T, 100 mm; C-I, 50 µm.