Scientists have discovered a new species of luminous creatures in the Red Sea, living in colonies as garlands of ‘fluorescent lanterns’ and emitting a green glow.
During the study of the biodiversity of coral reefs of the archipelago Farasan in Saudi Arabia, south of the Red Sea, researchers observed marine life under the ultraviolet (UV) light with yellow filters.
They found “fluorescent lanterns,” that were very similar to hydrae, but unlike their distant relatives who lead a solitary life in fresh water new species from the Red Sea form spreading colonies decorating miniature shells of gastropods Nassarius margaritifer (20-35mm in length) with garlands of green lights.
These molluscs bury themselves in the sediment during the day and at night crawl out to the surface to hunt other invertebrates.
Sea hydroids, unlike hydrae, are often found in colonies and can branch off tiny jellyfish. The unusual green glow of these hydrozoas (presumably, a new species of the genus Cytaeis, whose body length reaches 1.5mm) was revealed in the peristomal area of the body.
The researchers suggest that glow around the mouth of polyps may attract prey. “Fluorescent flashlights” may be visible to other invertebrates in the moonlight, and at sunset and sunrise.
Fluorescent proteins are widespread among the corals Anthozoa and hydroid jellyfishes, and also were found in some lancelets (Cephalochordata) and combjellies (Ctenophora).