sea sparkle

dinoflagellate

Also known as: Noctiluca miliaris, Noctiluca scintillans

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July 16, 2026

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Sea sparkle, scientifically known as Noctiluca scintillans, is a type of marine dinoflagellate that exhibits bioluminescence. Dinoflagellates are single-celled aquatic organisms with characteristics of both plants and animals, playing a crucial role in marine food chains.123

When disturbed, Noctiluca scintillans emits a blue-green light, a phenomenon that has historically been referred to as "sea sparkle" or "burning of the sea". This bioluminescence is a chemical reaction involving luciferin and luciferase. While beautiful, dense blooms of these organisms, visible as red or pink scums during the day, can be harmful to fish and other marine life. Some dinoflagellates are also known to produce potent toxins, contributing to phenomena like red tides.12435

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marine bioluminescence
notably the microscopic dinoflagellate Noctiluca scintillans, as well as some jellyfish. Many small crustaceans, such as the Vargula hilgendorfi (also known as Cypridina hilgendorfii), which is 3 to 4 mm (about 1/6 inch) long, become bioluminescent when disturbed. Many squids emit luminous clouds when threatened. Some species of fish…
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notably the microscopic dinoflagellate Noctiluca scintillans, as well as some jellyfish. Many small crustaceans, such as the Vargula hilgendorfi (also known as Cypridina hilgendorfii), which is 3 to 4 mm (about 1/6 inch) long, become bioluminescent when disturbed. Many squids emit luminous clouds when threatened. Some species of fish…
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Noctiluca
…consisting of a single species, Noctiluca scintillans (or N. miliaris), one of the most commonly occurring bioluminescent organisms in coastal regions of the world. The scintillating effect of Noctiluca’s bioluminescence, which is most conspicuous at night during a bloom (population increase), was historically a mysterious phenomenon, frequently contributing to what…
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…consisting of a single species, Noctiluca scintillans (or N. miliaris), one of the most commonly occurring bioluminescent organisms in coastal regions of the world. The scintillating effect of Noctiluca’s bioluminescence, which is most conspicuous at night during a bloom (population increase), was historically a mysterious phenomenon, frequently contributing to what…
Read More