Longhead Dreamer, Chaenophryne longiceps Regan, 1925

Scientific name: Chaenophryne longiceps
  • Updated
    30/03/21
  • Read time
    2 minutes
Chaenophryne longiceps Click to enlarge image
A 13cm long specimen of C. longiceps trawled during the NORFANZ expedition at a depth between 1635m and 1749m in international waters between Australia and New Zealand, May 2003 (CSIRO H6022-01). Image: NORFANZ
© NORFANZ

Fast Facts

  • Classification
    Genus
    Chaenophryne
    Species
    longiceps
    Family
    Oneirodidae
    Class
    Actinopterygii
    Subphylum
    Vertebrata
    Phylum
    Chordata
    Kingdom
    Animalia
  • Size Range
    The species grows to 17 cm in length.

Introduction

The Longhead Dreamer is a solitary species occuring widely in bathypelagic waters of the Indian, Pacific and Atlantic Oceans. The first dorsal fin of the female is modified to act as a lure to attract prey and the males seek females for mating through highly developed sense organs. Males (1.8 cm) attach themselves to the females (28 cm) through specialised tooth-bearing denticles but are not parasitic.

Identification

The Longhead Dreamer has a rounded body with a distinct illicium projecting from the snout. It is classified in the family Oneirodidae and can be distinguished from other anglerfish families by a combination of characters that include the placement of the illicium, the smooth snout and chin that lacks a barbel and the dorsal and anal fins with 4 to 8 rays.

A second species of Chaenophryne, C. draco, the Smooth Dreamer, is known from Australian waters. The two species can be separated by characteristics of the esca and by the number of pectoral fin rays. C. longiceps has 17-22 rays (rarely fewer than 18) versus 16-19 rays (rarely more than 18) in C. draco.

Chaenophryne longiceps
Esca of a 13 cm long specimen of C. longiceps trawled during the NORFANZ expedition at a depth between 1635 m and 1749 m in international waters between Australia and New Zealand, May 2003 (CSIRO H6022-01). Image: NORFANZ
© NORFANZ

Distribution

It occurs widely in bathypelagic waters of the Indian, Pacific and Atlantic Oceans.

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

Other behaviours and adaptations

The first dorsal fin of the female is modified to act as a lure to attract prey.

Breeding behaviours

The male seeks females for mating through highly developed sense organs. Males (1.8 cm) attach themselves to the females (28 cm) through specialised tooth-bearing denticles but are not parasitic.

References

  1. Bertelsen, E., & Pietsch, T.W. 1983. The Ceratioid Anglerfishes of Australia. Records of the Australian Museum. 35: 77-99.
  2. Pietsch, T. W. 1999. Oneirodidae. 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.
  3. Stewart, A.L. & T.W. Pietsch. 1998. The ceratioid anglerfishes (Lophiiformes: Ceratioidei) of New Zealand. Journal of the Royal Society of New Zealand. 28 (1): 1-37.