This solitary scleractinian coral, squat and cup-
shaped, colonized 'hardground' areas of the sea
floor during much of the Mesozoic Era. These
were areas where the sediment had become
saturated with minerals produced by the
decomposition of shelly material, resulting
in a solid, concrete-like sea bed.
Montlivaltia probably established itself
in such an environment by inhabiting
holes eroded by current- or wave-
borne pebbles or abandoned mollusc
borings. It is a moderately common
fossil of Triassic and Cretaceous rocks,
and it is found on all continents. Like all
coral polyps, it would extend its stinging
tentacles from its surrounding skeleton.