Glasshead Barreleye, Rhynchohyalus natalensis (Gilchrist & von Bonde 1924)
A Glasshead Barreleye, Rhynchohyalus natalensis, taken in a deep-sea trawl in the Southern Tasman Sea Abyssal Basin between 800-1000 m depth. The red arrows in the lower right figure indicate the notch in the cornea of the "second eye". Source: Adrian Flynn, in Partridge et al 2014 Proc. R. Soc. B 281: 20133223. License: CC by Attribution
The remarkable Glasshead Barreleye, found in the oceanic "twilight zone", has bi-directed eyes capable of seeing above and below. The barreleye has a conventional refractive lens on top of its head to see predators and prey that are silhouetted against the dim light filtering down from above. It also has a curved mirror-like lens and retina that sees the flashes of bioluminescence from fishes and invertebrates to the side and below, giving the fish a much larger field of view.
Glasshead Barreleye, Rhynchohyalus natalensis (Gilchrist & von Bonde 1924)
More Info
Distribution |
Recorded in Australia from off Norah head to off Nowra, New South Wales. Elsewhere, the species is circumglobal in temperate mesopelagic waters. |
Species Citation |
Hyalorhynchus natalensis Gilchrist & von Bonde, 1924. Rept Fish. Mar. Biol. Surv. Union South Africa 3(7): 4, pl. 1(1). Type locality: off Table Bay, South Africa, depth 135 fathoms. |
Author |
Dianne J. Bray |
Glasshead Barreleye, Rhynchohyalus natalensis (Gilchrist & von Bonde 1924)
References
Barnard, K.H. 1925. A monograph of the marine fishes of South Africa. Part 1. (Amphioxus, Cyclostomata, Elasmobranchii, and Teleostei — Isospondyli to Heterosomata). Annals of the South African Museum 21(1): 1-418 figs 1-18 pls 1-17
Bertelsen, E., Theisen, B. & Munk, O. 1965. On a postlarval specimen, anal light organ, and tubular eyes of the argentoid fish Rhynchohyalus natalensis (Glichrist and von Blonde). Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening i Kjøbenhavn 128: 357–371.
Cohen, D.M. 1964. Suborder Argentinoidea. In, Olsen, Y.H. (ed.) Fishes of the Western North Atlantic. Memoir. Sears Foundation of Marine Research 1(4): 1-70 figs 1-20
Gilchrist, J.D.F. & von Bonde, C. 1924. Special report No. 7. Deep-sea fishes procured by the S.S. Pickle (part 2). Report. Fisheries & Marine Biological Survey, Union of South Africa 3: 1-24 pls 1-6.
Okiyama, M. 1993. An atlas of the early stage fishes in Japan. Koeltz Scientific Books, Germany. 1154 pp. (in Japanese)
Partridge, J.C., R.H. Douglas, N.J. Marshall, W.-S. Chung, T.M. Jordan & H.-J. Wagner. 2014. Reflecting optics in the diverticular eye of a deep-sea barreleye fish (Rhynchohyalus natalensis). Proceedings of the Royal Society B 218(1782): doi: 10.1098/rspb.2013.3223 PDF
Paxton, J.R., Gates, J.E., & Bray, D.J. 2006. Opisthoproctidae. pp. 371-372 in Beesley, P.L. & Wells, A. (eds). Zoological Catalogue of Australia. Volume 35 Australia : ABRS & CSIRO Publishing Parts 1-3, 2178 pp.