The 'Globigerinida' are a common group of
foraminiferans that are found as marine
plankton (other groups are primarily benthic). They produce hyaline calcareous tests, and are known as fossils from the
Jurassic period onwards. The group has included more than 100 genera and over 400 species, of which about 30 species are extant. One of the most important genera is ''Globigerina''; vast areas of the ocean floor are covered with ''Globigerina'' ooze (named by Murray and Renard in 1873), dominated by the shells of planktonic forams.