Stoplight loosejaw

Stoplight loosejaw
Illustration of a stoplight loosejaw
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Stomiiformes
Family: Stomiidae
Subfamily: Malacosteinae
Genus: Malacosteus
Ayres, 1848
Northern stoplight loosejaw, Malacosteus niger, caught off Newfoundland

The stoplight loosejaws are small, deep-sea dragonfishes of the genus Malacosteus, classified either within the subfamily Malacosteinae of the family Stomiidae, or in the separate family Malacosteidae. They are found worldwide, outside of the Arctic and Subantarctic, in the mesopelagic zone below a depth of 500 meters (1,600 feet). This genus once contained three nominal species: M. niger (the type), M. choristodactylus, and M. danae, with the validity of the latter two species being challenged by different authors at various times. In 2007, Kenaley examined over 450 stoplight loosejaw specimens and revised the genus to contain two species, M. niger and the new M. australis.[1]

Malacosteus and the related genera Aristostomias, Chirostomias and Pachystomias are the only fishes that produce red bioluminescence. As most of their prey organisms are not capable of perceiving light at those wavelengths, this allows Malacosteus to hunt with an essentially invisible beam of light. Furthermore, Malacosteus is unique amongst animals in using a chlorophyll derivative to perceive red light.[1] The name Malacosteus is derived from the Greek malakos meaning "soft" and osteon meaning "bone".[2] Another common name for these fishes is "rat-trap fish", from the unusual open structure of their jaws.[3]

  1. ^ a b Cite error: The named reference kenaley was invoked but never defined (see the help page).
  2. ^ Hunter, R.; Williams, J.A. & Herrtage, S.J.H. (1897). The American Encyclopaedic Dictionary. R.S. Peale and J.A. Hill.
  3. ^ Ellis, R. (1996). Deep Atlantic: Life, Death, and Exploration in the Abyss. Alfred A. Knopf. ISBN 0-679-43324-4.