…a species of colonial brain coral (Faviidae) which occurs in shallow/moderate Caribbean waters. Great star coral colonies can grow quite large with colonies forming massive “boulders” over 5 feet (1.5 m) wide, with individual polyps the size of human thumbs! Like other corals great star corals are carnivorous, with polyps feeding on passing zooplankton.
The blue coral, Heliopora coerulea, is named for its distinctive, permanently blue skeleton, which is covered by greenish-grey or blue polyps. This species is the only living octocoral known to produce a massive hard skeleton similar to that of stony corals to which it is only remotely related.
Velella is a genus of free-floating hydrozoans that lives on the surface of the open ocean, worldwide, and is commonly known by the names by-the-wind sailor, purple sail, little sail, or simply Velella. The most common, and perhaps the only species encountered is Velella velella.