Neogloboquadrina pachyderma

Neogloboquadrina pachyderma is a Foraminifère discovered by Christian Gottfried Ehrenberg in 1861.

The species presents a rather broad tolerance of living conditions, but appreciates cool water and dense, with a weak vertical variation in temperature as of the limited seasonal variations - what locates its best habitat at the sub-polar latitudes at polar. One finds it in small quantities in tropical and subtropical water.

The rolling up of the shell (or test) of Neogloboquadrina pachyderma depends on the temperature of surface water:

sinistral rolling up (towards the left) in cold surface water - sub-polar habitat with polar
dextral rolling up (towards the line) in hot surface water - tropical habitat with subtropical

The dextrogyre form (dextral rolling up) perhaps considered as a subpopulation evolving/moving under not-optimal conditions. It is a good indicator of densities lower than 25.5 kg/m3.

This property makes this species an invaluable ally of the climatologists. Indeed, the observation of the fossil populations makes it possible to obtain a rather precise evaluation of the density and temperature of the sea water in which the individuals evolved/moved.

External bonds

http://fuhrmann-hilbrecht.de/Heinz/geology/HH1996/pachy.html

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