Description: Variety of D. brouweri with four, symmetrically disposed rays.
Remarks: Unlike D. asymmetricus, this form is very rare outside the mid Pliocene. It seems to have genuine first and last occurrences at, or very near to, the levels of the beginning and end of the D. asymmetricus acme. Within this range its abundance is closely related to that of D. asymmetricus (Bergen 1984, Backman 1986, Chapman & Chepstow-Lusty 1997). These two discoasters are also of similar size in any one sample.
Range: NN14 to 16.
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