The species was benthonic (bottom-dwelling), within the photic zone in warm, shallow marine waters, such as a reef environment.

This was a single-celled organism, with biology, structure and function of the cell thought to be similar to, although somewhat more complex (with a greater number of organelles) than a modern day amoeba.

However, these forms and the foraminifera in general, display a complexity of form and function more commonly associated with somewhat higher forms of life, as evidenced by their capacity to construct an architecturally complex shell.


Average size is around 2-3cm in diameter for this species, although other species of Nummulites commonly reach 6cm in diameter.


There is some fossil evidence to support the theory that early growth was fairly rapid, probably in an attempt to quickly increase size beyond that favoured by some predators.


As with modern foraminifera, strategies of reproduction involved alternating sexual (gamont) and asexual (agamont) generations, resulting in a population consisting of two distinct size groups (dimorphism).

Asexual reproduction resulted in forms having a small initial chamber (proloculus), while sexual reproduction resulted in a large (megalospheric) proloculus.

The sexually produced A-form generation produced fewer chambers and is smaller than the asexual, B-form, generation.


Free-swimming gametes leave the shell of asexually produced adults.