Southern Loosejaw, Malacosteus australis Kenaley 2007


Other Names: Black Hinged-head, Black Loosejaw, Blunthead Dragonfish

Southern Stoplight Loosejaw, Malacosteus australis. Source: Rudie H. Kuiter / Aquatic Photographics. License: All rights reserved

Summary:
A species of barbeled dragonfish found in the deep waters off southern and south-eastern Australia.

Cite this page as:
Bray, D.J. 2017, Malacosteus australis in Fishes of Australia, accessed 12 Jul 2020, http://136.154.202.208/home/species/1807

Southern Loosejaw, Malacosteus australis Kenaley 2007

More Info


Features

Dorsal fin 16-21; Anal fin 18-23; Pectoral fin 3-5; Pelvic fin 6; Branchiostegal rays 7-9; Vertebrae 45-51.

Size

Maximum known length is 16.6 cm for a male and 19.2 cm for a female.

Feeding

Feeds on mesopelagic fishes and invertebrates, especially copepods. The Southern Loosejaw presumably uses the large accessory orbital photophore (AO) in employing a far-red visual system as part of its foraging strategy (Kenaley 2007).

Remarks

Red light cannot penetrate into the deep oceanic waters, and as a result, most animals living in the deep-sea have lost the ability to see red. Therefore, the vast majority of bioluminescent animals living in the deep-sea produce a blue light. Not only does Malacosteus have a photophore just behind the eye that produces a blue light, they also have a large elliptical photophore under the eye that produces red bioluminscence. This allows them to shine a red light that cannot be seen by their unsuspecting prey, giving them a huge advantage in their dark environment.

Similar Species

Differs mainly from Malacosteus niger in having a a smaller postorbital photophore in both sexes, lower numbers of lateral photophores, somewhat smaller jaws and a fleshy orbit.

Etymology

The specific name australis is from the Latin austral, meaning "southern" in reference to the southern distribution of this species.

Species Citation

Malacosteus australis Kenaley 2007, Copeia 2007(4): 893, Figs. 4-5. Type locality: Tasman Sea, off Brush Island, 35°36'S, 150°55'E, depth 650-2000 m.

Author

Bray, D.J. 2017

Resources

Australian Faunal Directory

Southern Loosejaw, Malacosteus australis Kenaley 2007

References


Kenaley, C.P. 2007. Revision of the stoplight loosejaw genus Malacosteus (Teleostei: Stomiidae:, Malacosteinae), with description of a new species from the temperate Southern Hemisphere and Indian Ocean. Copeia 2007(4): 886-900.

Kenaley, C.P., Harold, A.S. & Gomon, M.F. 2008. Family Stomiidae. pp. 240-254 in Gomon. M.F., Bray, D.J. & Kuiter, R.H (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.

Quick Facts


CAAB Code:37110001

Biology:Bioluminescent

Depth:500 to over 2000 m

Habitat:Mesopelagic

Habitat:Mesopelagic, bathypelagic

Max Size:19+ cm SL

Species Image Gallery

Species Maps

CAAB distribution map