Allogromiida

The Allogromiida are a group of monothalamous (single-chambered), mostly organic-walled foraminiferans, including some that produce agglutinated tests (Lagynacea). Genetic studies have shown that some foraminiferans with agglutinated tests, previously included in the Textulariida or as their own order Astrorhizida, also belong here. Allogromiids produce relatively simple tests, usually with a single chamber, similar to those of other protists such as Gromia. They are found in both marine and freshwater forms, and are the oldest forams known from the fossil record.