Type Species

Miravetesina favula Grün in Grün & Allemann, 1975

Description

The elliptical placolith has a cretarhabdid pelaga and a central area spanned by an axial cross that may be slightly rotated relative to the axis of the placolith. The axial cross may be distinct (e.g. Miravetesina favula) or indistinct (e.g. Miravetesina culverensis) and supports a distal process. The inter-cross area is occupied by circular pores arranged in at least two complete concentric cycles.

Optical Properties

In plan view under crossed polars, the pelaga exhibits first-order, slightly greyish-white interference colours, showing inclined extinction and length-fast (–) elongation. The central area displays whitish-grey interference colours.

References

Grün, W. & Allemann, F. 1975. The Lower Cretaceous of Caravaca (Spain): Berriasian Calcareous Nannoplankton of the Miravetes Section (Subbetic Zone, Prov. of Murcia). Eclogae Geologicae Helvetiae, 68: 147-211.