Miliolidae

Miliolidae is a large and diverse family of foraminifera, which are single-celled eukaryotic organisms. These organisms are characterized by their calcareous shells, known as tests, which are typically composed of calcium carbonate. The name Miliolidae is derived from the Latin word "milium," meaning millet, referring to the common shape of some of their chambers.

A distinguishing feature of Miliolidae is the arrangement of their chambers. Many species exhibit a quinqueloculine or serpentine coiling pattern, where chambers are added in alternating planes, giving the test a twisted appearance. Other arrangements, such as triloculine (three visible sides) and bifiserial (two rows of chambers), also occur within the family. The aperture, the opening through which the pseudopodia extend, is often distinctive, frequently featuring a tooth-like projection.

Miliolids are predominantly marine organisms and are found in a wide range of environments, from shallow coastal waters to the deep sea. They are particularly abundant in tropical and subtropical regions and are common in both planktonic and benthic communities. Some species are known to tolerate brackish or hypersaline conditions.

As foraminifera, Miliolidae play a role in marine ecosystems. Their calcareous tests contribute to the calcium carbonate sediment on the seafloor. Fossilized tests of Miliolidae are important in paleontology and biostratigraphy, helping to date sedimentary rock layers. Economically, they can be indicators of past environmental conditions, useful in oil exploration.