Globigerinoides
Globigerinoides altiaperturus
Globigerinoides apertasuturalis
Globigerinoides bispherica
Globigerinoides bisphericus
Globigerinoides conglobatus
Globigerinoides elongatus
Globigerinoides gomitulus
Globigerinoides hyalinus
Globigerinoides inusitatus
Globigerinoides minuta
Globigerinoides pyramidalis
Globigerinoides quadrilobatus
Globigerinoides ruber
Globigerinoides sacculifer
Globigerinoides sicanus
Globigerinoides tenella
Globigerinoides trilobus
Globigerinoides is an extant genus of shallow-water planktonic foraminifera of family Globigerinidae. First appearing in the Oligocene these foraminifera are found in all modern oceans. Species of this genus occupy the euphotic zone, generally at depths between 10-50m, in waters which cover a range of salinities and temperatures. They are a shorter lived species, especially when compared to Globorotalia genus. As a genus Globigerinoides is widely used in various fields of research including biostratigraphy, isotope geochemistry, biogeochemistry, climatology, and oceanography.
The foraminifera of genus Globigerinoides are all shallow-water species with spinose forms made of hyaline calcite. Most species have trochospiral chamber arrangement, though some species exhibit further complexity with streptospiral chamber arrangement. Tests are composed of thin perforated walls, with very large pores, and spines being added at the end of individual chamber formation. Certain species are known to produce a modified type of calcium carbonate, 18O enriched-gametogenic calcite, at the end of their life cycle. Prior to gametogenesis and the production of the final calcite layer, the spines are reabsorbed by the foraminifera leaving behind a test that is heavily calcified, and shows the remnants of spine holes. As with other amoeboids these foraminifera utilize pseudopodia. Pseudopodia are widely used throughout their entire lifecycle for various purposes including feeding, movement, protection, and chamber formation.
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