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Common name: Sea Fire-Fly
Scientific name: Vargula hilgendorfii

Kingdom: Animalia
Phylum: Arthropoda
Class: Ostracoda
Order: Myodocopina
Family: Cypridinidae
Genus: Vargula
Species: V. hilgendorfii


When you think of fire flies you would picture them in a meadow, however, there are some species that live in other habitats. Vargula hilgendorfii, also known as the Sea Fire-Fly, lives in the Pacific coast around Japan. They have seven pairs of different body parts; these body parts specialize their organs. I want to emphasize the importance of this animal because it is greatly unknown to many people.

The Sea Fire-Fly is a very interesting and an unusual animal. They are kind of small; only three millimeters long. The Sea Fire-Fly produces a blue colored light that glows in the dark! This light is formed when a specialized chemical reaction happens. They also have many adaptations, one of these is when they feel threatened they will use there large appendages to quickly go into the sand. They will also use them to get out of the sand into the water. One way you can identify this animal is by their glowing blue color. As you can see the Sea Fire-fly is interesting and unusual.

Even though you may not be able to see these animals there are still a great number of them.  They are found in the pacific coast around Japan, in the day time they hide themselves in the sand. Scientist don’t know exactly how many there are but they do know they aren’t considered threatened or endangered. They also know that this animal stays pretty stable with the population. Consequently this animal is doing pretty well in society.

The sea Fire-Fly is both a scavenger and a consumer. The place in the food web is still unknown for this species, but they do know that they eat mainly meats. Some meat that they eat is they scavenge dead fish and eat sandworms. One of the predators of this animal is fish. The Sea Fire-Fly escapes from the fish by using there large appendages to quickly move in and out of the sand. In conclusion this animal is a scavenger and a consumer.

The importance of the Sea Fire-Fly is so there won’t be many dead fish lying around the coast. I think what stood out to me the most about this animal is its blue glowing color. This is interesting because no other animal that I know glows! I hope that you will think more about this animal because this animal plays an important job in our planet; by breaking down the great numbers of dead fish.

Author: Jordan B.
Date published: 4/2013

Sources:,, hilgendorfii
Photo Credit:

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