Globigerina is a marine microorganism characterized by its spherical, coiled shell known as a
test. The test is composed of chambers that are not elongated radially but are rounded and trochospiral. As the organism grows, these chambers enlarge rapidly, typically reaching three to five chambers in the final whorl. The test of Globigerina is constructed from
calcareous material and contains pores in a cylindrical pattern, allowing for the exchange of substances. While the organism is alive, the test surface is adorned with numerous slender spines. However, upon death or fossilization, these spines break, leaving behind short, blunt remnants that create a rough texture on the surface, referred to as a
hispid appearance. The aperture, or opening, of the test is located at the top and takes the form of a high umbilical arch. This aperture may be accompanied by an imperforate rim or a narrow lip around its edges. Notably, there are no secondary apertures present in the test structure. ==Species==