foraminifera test foraminifera test foraminiferal tests are the tests (or shells) of foraminifera. foraminiferan tests (ventral view) foraminifera (forams for short) are single-celled predatory protists, mostly marine, and usually protected with shells. these shells, often called tests, can be single-chambered or have multiple interconnected chambers; the cellular machinery is contained within the shell. so important is the test to the biology of foraminifera that it provides the scientific name of the group—foraminifera, latin for "hole bearers", referring to the pores connecting chambers of the shell in the multi-chambered species. foraminiferal tests are usually made of calcite, a form of calcium carbonate (caco3), but are sometimes made of aragonite, agglutinated sediment particles, chitin, or (rarely) of silica. other foraminifera lack tests altogether. over 50,000 species are recognized, both living (6,700 - 10,000) and fossil (40,000). they are usually less than 1 mm in size, but some are much larger, the largest species reaching up to 20 cm. most forams are benthic, but about 40 extant species are planktic. the hard nature of most foraminiferal tests leads to an excellent fossil record, and they are widely researched to infer information about past climate and environments. external video foraminiferans foraminiferal networks and growth background part of a series related tobiomineralization general mineralized tissues remineralisation biocrystallization biointerface biofilm exoskeletons (shells) arthropod exoskeleton cuticle brachiopod shell cephalopod shell cirrate shell cuttlebone gladius lorica choanoflagellate lorica protist shell coccosphere coccolith diatom frustule foraminifera test testate amoebae seashell echinoderm stereom mollusc shell nacre chiton shell gastropod shell small shelly fauna scaly-foot snail shell estuary shells sponge spicule test endoskeletons (bones) vertebrate skeleton bone mineral ossification teeth, scales, tusks etc limpet teeth otolith otolithic membrane scale microfossils tusk calcification amorphous calcium carbonate marine biogenic calcification calcareous nannofossils aragonite oolitic aragonite sand aragonite sea calcite microbial calcite precipitation calcite sea great calcite belt silicification biogenic silica siliceous ooze diatomaceous earth other forms bone bed kerogen alginite oil shale phosphate phosphorite pyrena related mineral evolution in soil mineralization immobilization ballast minerals magnetofossil magnetosome magnetotactic bacteria magnetoreception microfossils engrailed gene druse cupriavidus metallidurans biomineralising polychaetes mineral nutrients microbial mat fossilization permineralization petrifaction burgess shale preservation category