Amphinomidae, also known as the bristle worms or sea mice, are a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of marine polychaetes, many species of which bear

chaeta A chaeta or cheta (from Greek χαίτη “crest, mane, flowing hair"; plural: chaetae) is a chitinous bristle or seta found in annelid worms, (although the term is also frequently used to describe similar structures in other invertebrates such ...

e mineralized with carbonate. The best-known amphinomids are the fireworms, which can cause great pain if their toxin-coated chaetae are touched or trodden on. Their relationship to other polychaete groups is somewhat poorly resolved.

Complanine

Complanine Complanine is a quaternary ammonium compound isolated from the marine fireworm ''Eurythoe complanata In Greek mythology, Eurythoe is one of the Danaïdes. She is one of the possible mothers of Oenomaus by Ares;Scholia on Apollonius Rhodius, ...

is a

quaternary ammonium salt In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cat ...

that has been isolated from the marine fireworm ''

Eurythoe complanata In Greek mythology, Eurythoe is one of the Danaïdes. She is one of the possible mothers of Oenomaus by Ares;Scholia on Apollonius Rhodius, ''Argonautica'' 1.752. she is alternatively the mother of Hippodamia (mythology), Hippodamia by Oenomaus.T ...

''. It causes an inflammatory effect upon contact with the skin or mucous membranes. It was previously known that handling the fireworm caused it to release a chemical that induces

inflammation Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...

of the skin of marine predators and mammals (including humans). Complanine was the first compound isolated from the fireworm which causes these effects. It is presumed that this compound's function is to deter predators of the fireworm.

Species