The similar-looking corallimorphan covers large areas of dead coralline limestone boulders on Bermuda reefs.
They also gave detailed descriptions of associated lithologies, noting that the coralline interval lies some tens of meters below the calcareous shale that contains ‘Paratrachyceras ammonoids’.
Sandy flats with occasional coralline outcrops dominate the bottom topography.
The beach was conspicuous, not just because of the brilliance of its coralline sand but because of the absence of the waste products of human society.
Two coralline pillars shoulder their way up from the deep and barge through throngs of fish to emerge swathed in surf, snarling in the face of the currents that dominate this coast.
At first they appear to have produced vases with a black glaze, but this soon gave place to a red coralline colour.
Archaeocyathids, which are possible representatives of coralline sponges, have a secondary calcareous skeleton of high Mg-calcite and are possibly derived from demosponges.
Rhodoliths are a type of algae that secretes a coralline skeleton, a bit like a coral.
Many non-geniculate coralline algae have been suggested to actively inhibit colonization of epiphytes by shedding epithallial cells.
Diversification of coralline algae during the Cretaceous and Cenozoic is well documented.