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Mesonychoteuthis Robson, 1925

Mesonychoteuthis hamiltoni Robson, 1925

Richard E. Young and Katharina M. Mangold (1922-2003)
The genus contains a single species.
Containing group: Taoniinae


Mesonychoteuthis hamiltoni is the largest of all cranchiid species with adults reaching over 2 m in mantle length (Nesis, 1982). It is a circumpolar Antarctic species with young found north to the subtropical convergence (Nesis, 1982).


A taoniin ...


  1. Arms
    1. Hooks present on arms.
       image info

      Figure. Oral view of half of the arm crown (arms I-IV, arm I at top) of a juvenile M. hamiltoni, 86 mm ML. Drawing from Voss (1980), p. 395.

  2. Tentacles
    1. Tentacular club with hooks.
    2. Diagonally set pairs of suckers and pads on distal 2/3 of tentacular stalk.

  3. Funnel
    1. Funnel valve absent.
    2. Funnel organ: Dorsal pad with three papillae.

  4. Mantle
    1. Tubercles absent in adults, present in paralarvae and juveniles.

  5. Fins
    1. Fins ovate, without anterior lobes.
    2. Fins terminal.

  6. Photophores
    1. Two ocular photophores: crescent-shaped medial photophore and small, oblong lateral photophore within concavity of first.
    2. Arm tip photophores probably absent.


This is the only cranchiid that has hooks on the arms. Characteristics are from Voss (1980).

Life History

The young stages were described by McSweeny (1970). Hooks first appear on the arms at about 45 mm ML.

 image info
 image info

Figure. Top - Dorsal view of an advanced paralarva of M. hamiltoni, 23 mm ML. Bottom - Ventral view of a juvenile of M. hamiltoni, 86 mm ML. Drawings from Voss (1980, p. 395, fig. 10 c, b).


M. hamiltoni is known only from Antarctic waters. A map of its distribution can be found here.


Nesis, K. N. 1982/87. Abridged key to the cephalopod mollusks of the world's ocean. 385+ii pp. Light and Food Industry Publishing House, Moscow. (In Russian.). Translated into English by B. S. Levitov, ed. by L. A. Burgess (1987), Cephalopods of the world. T. F. H. Publications, Neptune City, NJ, 351pp.

McSweeny, E. S. 1970. Description of the juvenile form of the Antarctic squid Mesonychoteuthis hamiltoni Robson. Malacologia, 10: 323-332.

Voss, N. A. 1980. A generic revision of the Cranchiidae (Cephalopoda; Oegopsida). Bull. Mar. Sci., 30: 365-412.

Title Illustrations
Scientific Name Mesonychoteuthis hamiltoni
Reference modified from Voss, N. A. 1980. A generic revision of the Cranchiidae (Cephalopoda; Oegopsida). Bull. Mar. Sci. 30:365-412.
Sex f
Life Cycle Stage subadult
Size 1250 mm ML
Copyright © 1980 Bulletin of Marine Science
Scientific Name Mesonychoteuthis hamiltoni
Location New Zealand waters
Comments Steve O'Shea is standing next to the squid.
Copyright © Kat Bolstad
About This Page
Drawings from Voss (1980) Printed with the Permission of the Bulletin of Marine Science.

Richard E. Young

Dept of Oceanography
University of Hawaii
Honolulu, Hawaii 96822

Katharina M. Mangold (1922-2003)

Citing this page:

Young, Richard E. and Mangold (1922-2003), Katharina M. 1999. Mesonychoteuthis Robson, 1925. Mesonychoteuthis hamiltoni Robson, 1925. Version 01 January 1999 (under construction). http://tolweb.org/Mesonychoteuthis_hamiltoni/19556/1999.01.01 in The Tree of Life Web Project, http://tolweb.org/

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