Globothalamea comprises a class of multichambered

foraminifera Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and ot ...

based in part on SSU rDNA evidence; the other is

Tubothalamea Tubothalamea is a taxonomic class established for foraminiferans with tubular chambers. Includes the porcelaceous and agglutinated Miliolida and the monocrystalline and agglutinated Spirillinida. It is one of two classes of multichambered foramin ...

. Six orders are included, which vary notably in composition, wall structure, and chamber arrangement. The Lituolida, Loftusiida, and Textulariida (as emended) have tests (shells) of agglutinated matter, glued together by various cements, but differ in chamber arrangement, wall structure, and complexity. In contrast the

Carterinida Carterinida is an order of multi-chambered foraminifera within the Globothalamea. Members of this order form hard tests out of thin calcite rods known as spicules, which are held together by a proteinaceous matrix. The spicules of carterinids ha ...

, Robertinida and Rotaliida, with buliminids lumped into the Rotaliida, have calcareous tests. Those of rotaliid genera, which vary considerably, are of perforate hyaline (glassy)

calcite Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...

. in contrast the Carterinida have tests composed of bundled calcite spicules. The Robertida differ in being composed, instead, of aragonite. Foraminifera genera and their description
A.R. Loeblich jr & H. Tappan, 1988. e-book. Subclass Textulariia * Orders: Lituolida – Loftusiida – Textulariida Unassigned * Orders:

– Robertinida – Rotaliida

References

{{Taxonbar, from=Q19844835 Rhizaria classes