''Eurythoe complanata'', the iridescent fireworm, is a species of

polychaete Polychaeta () is a paraphyletic class of generally marine Annelid, annelid worms, common name, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called c ...

s belonging to the family

Amphinomidae Amphinomidae, also known as the fireworms, bristle worms or sea mice, are a family (biology), family of marine polychaetes, many species of which bear chaetae mineralized with carbonate. The best-known amphinomids are the fireworms, which can ca ...

. It inhabits

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in group ...

s, such as ''

Heliopora ''Heliopora'' is a genus of cnidarian in the family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis ...

'' reefs, in the

Marshall Islands The Marshall Islands, officially the Republic of the Marshall Islands, is an island country west of the International Date Line and north of the equator in the Micronesia region of the Northwestern Pacific Ocean. The territory consists of 29 c ...

. It is typically found in shallow, warm

tropical The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

waters near rocks and

coral Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

Description

The iridescent fireworm can be found in colors that vary from gray to green to pink. This species can grow to be up to long. It has tufted

branchiae A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

, used for

respiration Respiration may refer to: Biology * Cellular respiration, the process in which nutrients are converted into useful energy in a cell ** Anaerobic respiration, cellular respiration without oxygen ** Maintenance respiration, the amount of cellul ...

, starting on the second segment of its body and is located along the rest of the body. This species also has bristles along its body that produce a

toxin A toxin is a naturally occurring poison produced by metabolic activities of living cells or organisms. They occur especially as proteins, often conjugated. The term was first used by organic chemist Ludwig Brieger (1849–1919), derived ...

that “stings”. It uses this as a defense mechanism against different predators and can also use into stun prey. It is a

carnivorous A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose nutrition and energy requirements are met by consumption of animal tissues (mainly mu ...

species feeding on

sponge Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a basal clade and a sister taxon of the diploblasts. They are sessile filter feeders that are bound to the seabed, and a ...

mollusks Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The num ...

, and even other

worm Worms are many different distantly related bilateria, bilateral animals that typically have a long cylindrical tube-like body, no limb (anatomy), limbs, and usually no eyes. Worms vary in size from microscopic to over in length for marine ...

s. It can ingest its food all at once by expanding its lip by 4-5 times longer. It reproduces both sexually and asexually, by regeneration.

Distribution and habitat

''Eurythoe complanata'' can be found in most warm, tropical and subtropical waters. This includes areas such as the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

, the

Atlantic Ocean The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the ...

, and the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

. This species can be found up to depths of . It is usually found in shallow waters near rocks, boulders, coral, and even in small rock pools.

References

Errantia Animals described in 1766 {{Improve categories, date=November 2024