Chiastozygus litterarius

Discolithus litterarius Górka, 1957

sensu Chiastozygus litterarius Bown et al. in Bown 1998; Pl. 5.7, Fig.3

sensu Chiastozygus litterarius Burnett in Bown 1998; Pl. 6.3, Fig.5

sensu Chiastozygus fessus Salomon, 1999; The Calcite Palace. Website

sensu Chiastozygus litterarius Lees & Bown, 2005; Pl.1, Figs. 25-26.

sensu Chiastozygus litterarius Kanungo et al., 2020; Fig.4.1

Holotype/lectotype: Zygolithus litterarius (Górka, 1957) Reinhardt & Górka, 1967

Species of Chiastozygus are composed of a double wall and a symmetrical diagonal cross whose arms are divided into two halves and thicken where they meet the inner wall, collectively supporting a distal process.

In plan view under crossed polars, the walls and the diagonal cross remain in constant extinction, except for the thickened termini of the cross, which display birefringence together with the distal process.

This species is commonly assigned to Chiastozygus litterarius (see synonyms), but its conformity with the lectotype designated by Reinhardt & Górka (1967) is open to question.

Bown, P. R. & Cooper, M. K. E. 1998. Jurassic. In: Bown, P. R. (Ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 34-85.

Burnett, J. A. 1998. Upper Cretaceous. In: Bown, P. R. (Ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 132-199.

Górka, H. 1957. Les Coccolithophoridés du Maestrichtien supérieur de Pologne. Acta Palaeontologica Polonica. 2: 239-284

Kanungo, S., Bown, P. R. & Gale, A. S. 2020. Cretaceous (Albian-Turonian) calcareous nannofossil biostratigraphy of the onshore Cauvery Basin, southeastern India. Cretaceous Research. 118 (2021): 1-22

Lees, J.A., Bown, P.R. 2005. Upper Cretaceous calcareous nannofossil biostratigraphy, ODP Leg 198 (Shatsky Rise, Northwest Pacific Ocean). Proceedings of the Ocean Drilling Program. Scientific Results. 198: 1-60.

Manivit, H. ,1971. Nannofossiles calcaires du Crétacé francais (Aptien-Maestrichtien). Essai de Biozonation appuyée sur les stratotypes. PhD thesis, Université de Paris pp. ?-?

Reinhardt, P. & Górka, H. 1967. Revision of some Upper Cretaceous Coccoliths from Poland and Germany. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 129(3): 240-256.

Salomon, R. 1999. The Calcite Palace. Website - https://ina.tmsoc.org/gallerie