Planorbulinacea
Planorbulinacea Temporal range: Early Cretaceous - Recent. | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
(unranked): | SAR |
(unranked): | Rhizaria |
Phylum: | Retaria |
Subphylum: | Foraminifera |
Order: | Rotaliida |
Superfamily: | Planorbulinacea Schwager, 1877 |
Families | |
Bisacciidae |
Planorbulinacea is a superfamily of rotalliid Foraminifera that has been extant since the Early Cretaceous (Berriasian), characterized by trochospiral tests, at least in early stage but which later may become uncoiled. The test wall is of perforate hyaline calcite, commonly optically radial in structure, with crystallographic c-axes perpendicular to the surface. The apertural face may be imperforate; the aperture interiomarginal and extraumbilical-umbilical to nearly equatorial in coiled forms, subterminal in uncoiled forms.
The Planorbulinacea unites six families which are distinguished primarily by their morphological differences.
References
- Modern Foraminifera Barun K. Sen Gupta 1999 (ed).
- Planorublinacea, Loeblich & Tappan, 1988.
- Sarcodina Chiefly "Thecamoebians" and Foraminiferida; Treatise on Invertebrate Paleontology, Part C Protista 2. Geological Society of America and University of Kansas Press. A. R. Loeblich and H.Tappan, 1964.
This article is issued from Wikipedia - version of the Saturday, December 26, 2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.