Globigerina
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Globigerina Temporal range: Middle Jurassic - Recent. |
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| Illustration of Globigerina ooze | |
| Scientific classification | |
| Domain: | Eukaryota |
| (unranked): | SAR |
| (unranked): | Rhizaria |
| Superphylum: | Retaria |
| Phylum: | Foraminifera |
| Order: | Globigerinida |
| Family: | Globigerinidae |
| Genus: |
Globigerina d'Orbigny, 1826 |
Globigerina is a genus of planktonic Foraminifera that have populated the world's oceans since the Middle Jurassic.
Vast areas of the ocean floor are covered with Globigerina ooze, dominated by the foraminiferous shells of Globigerina and other Globigerinida. The name was originally applied to mud collected from the bottom of the Atlantic Ocean when planning the location of the first transatlantic telegraph cables and it was mainly composed of the shells of Globigerina bulloides.
Globigerina has a globose, trochospirally enrolled test composed of spherical to ovate but not radially elongate chambers that enlarge rapidly as added, commonly with only three to five in the final whorl. The test (or shell) wall is calcareous, perforate, with cylindrical pores. During life the surface has numerous long slender spines that are broken on dead or fossil shells, the short blunt remnants resulting in a hispid surface. The aperture a high umbilical arch that may be bordered by an imperforate rim or narrow lip. No secondary apertures.
Globigerina includes the following species (extinct species marked with a dagger, †)
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