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Gonatopsis Sasaki, 1920

Tsunemi Kubodera, F. G. Hochberg, Richard E. Young, and Michael Vecchione
taxon links [down<--]Gonatidae [up-->]Gonatopsis borealis [up-->]Gonatopsis japonicus [up-->]Gonatopsis makko Interpreting the tree
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Containing group: Gonatidae



A gonatid ...


  1. Arms
    1. Hooks in medial two armature series on arms I-III.

  2. Tentacles
    1. Tentacles absent beyond early juvenile stages.
       image info

      Figure. Oral view of the brachial crown of Gonatopsis borealis, 65 mm ML, off Aleutian Islands, preserved. White numerals identify the arms. Note that there is no trace of tentacles between arms III and IV. Photograph by R. Young.

  3. Head
    1. Radula with teeth in 5 or 7 series depending on species.

  4. Mantle
    1. Mantle tissue muscular or flabby depending on species.

  5. Fins
    1. Fins rhomboid or sagittate in shape depending on species.

  6. Photophores
    1. Photophores absent.


Gonatopsis is divided into two subgenera on the basis of the radular structure. G. (Gonatopsis) with a five-tooth radula and G. (Boreoteuthis) with a seven-tooth radula.

Species / Character  Habitat  Numerous sucker series at arm tips  Radular teeth  Arm length  Tail length 
G. borealis
North Pacific   No  7 40-50% ML  No tail 
G. japonicus  Japanese waters   No  5 55% ML  long 
G. makko  Northern-, western North Pacific   No  5 65% ML  very short 
G. octopedatus  Western North Pacific
 Yes  5 80-85% ML  No tail 
G. sp. A  Eastern North Pacific   Yes  ?  ?  ?
G. okutanii ? * Western North Pacific   No  5 ca. 100 % ML   ?
*Does not belong in Gonatopsis; tentacles apparently absent only in spent females. Correct genus uncertain.

Life History

Tentacles are present in paralarvae but are lost at different early stages depending on the species (Nesis, 1973).

 image info

Figure. Ventral view of a paralarva of G. borealis (bottom), 9 mm ML and an oral view of the paralarval tentacular club (top), 7 mm ML, off Southern California, U.S.A. Drawings from Young (1972).


Young, R.E. 1972. The Systematics and Areal Distribution of Pelagic Cephalopods from the Seas off Southern California. Smithsonian Contributions to Zoology, 97:159 pages.

Title Illustrations
Scientific Name Gonatopsis borealis
Location Off Southern California, U.S.A.
Reference Young, R.E. 1972. The Systematics and Areal Distribution of Pelagic Cephalopods from the Seas off Southern California. Smithsonian Contributions to Zoology, 97:159 pages.
View Ventral
Size 240 mm ML
Copyright © 1972 Richard E. Young
About This Page

Tsunemi Kubodera
National Science Museum, Tokyo, Japan

F. G. Hochberg
Santa Barbara Museum of Natural History, Santa Barbara, California, USA

Richard E. Young
University of Hawaii, Honolulu, HI, USA

National Museum of Natural History, Washington, D. C. , USA

Citing this page:

Kubodera, Tsunemi, Hochberg, F. G., Young, Richard E., and Vecchione, Michael. 2006. Gonatopsis Sasaki, 1920. Version 30 May 2006 (under construction). http://tolweb.org/Gonatopsis/19764/2006.05.30 in The Tree of Life Web Project, http://tolweb.org

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