Black Dragonfish, Idiacanthus atlanticus Click to enlarge image
Head of a Black Dragonfish collected on the NORFANZ expedition at a depth of approximately 1000m, May 2003. Image: Mark McGrouther
© NORFANZ

Fast Facts

  • Classification
    Species
    atlanticus
    Genus
    Idiacanthus
    Subfamily
    Idiacanthinae
    Family
    Stomiidae
    Order
    Stomiiformes
    Class
    Actinopterygii
    Subphylum
    Vertebrata
    Phylum
    Chordata
    Kingdom
    Animalia
  • Size Range
    Females grow to 40 cm in length, but males reach a maximum length of only 5 cm.

Introduction

The Black Dragonfishes are long, slender fishes which live in mesopelagic to bathypelagic waters down to depths of about 2000 m.

Identification

The Black Dragonfishes are long, slender fishes that are sexually dimorphic. The image shows a female with its small eyes, chin barbel, and long fang-like teeth. The male is much smaller. It lacks teeth, lacks the chin barbel, has a non-functional gut, and is dark brown rather than black.

The species has tiny photophores scattered over its body and two rows of larger photophores along the side of the body. The chin barbel of the female has a a slender luminous tip. This may be used to attract prey.

Larval Black Dragonfishes are most unusual. They are long, slender, transparent fishes that have their eyes at the ends of long stalks which can be up to half the length of the body.

Habitat

Black Dragonfishes live in mesopelagic to bathypelagic waters down to depths of about 2000 m.

Distribution

The species occurs in subtropical and temperate marine waters of the southern hemisphere. The subfamily Idiacanthinae contains three species, two of which, Idiacanthus fasciola Peters, 1877 and Idiacanthus atlanticus occur in Australian waters.

The map below shows the Australian distribution of the species based on public sightings and specimens in Australian Museums. Click on the map for detailed information. Source: Atlas of Living Australia.



Feeding and diet

It eats mostly other fishes.

Other behaviours and adaptations

Like many deepsea fishes, the Common Black Dragonfish has photophores that can produce light.

References

  1. Brauer, A. 1906. Die Tiefsee-Fische. I. Systematischer Teil. In: C. Chun. Wissenschaftl. Ergebnisse der deutschen Tiefsee-Expedition "Valdivia," 1898-99. Jena. v. 15: 1-432, Pls. 1-18.
  2. Gomon, M.F & E.M. Robertson. in Gomon, M.F, C.J.M. Glover & R.H. Kuiter (Eds). 1994. The Fishes of Australia's South Coast. State Print, Adelaide. Pp. 992.
  3. Harold, A.S. 1999. Idiacanthidae. in Carpenter, K.E. & V.H. Niem (Eds). FAO Species Identification Guide for Fishery Purposes. The Living Marine Resources of the Western Central Pacific. Volume 3. Batoid fishes, chimaeras and bony fishes part 1 (Elopidae to Linophrynidae). FAO, Rome. Pp. iii-vi, 1398-2068.