Braarudosphaera bigelowii is an extant species of unknown affinities which produces 12 pentagonal plates. (N.B. This drawing differs from the others in that it represents the entire exoskeltal sphere rather than a single lith).
Each individual pentalith is formed of five segments, with tangential c-axes. Braarudosphaera ranges back to the mid Cretaceous, and related forms to the earliest Cretaceous.
Since the affinities of the Braarudosphaera organism are uncertain it is not clear that the plates it produces are homologous with coccoliths so the neutral term nannolith is applied to them.