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Gonatopsis Sasaki, 1920

Richard E. Young, Michael Vecchione, and Tsunemi Kubodera
taxon links [down<--]Gonatidae 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 in subadult stage.

  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 subgeneraa on the basis of the radular structure. G. (Gonatopsis) octopedatus and G. (Gonatopsis) japonicus have a five-tooth radula while G. (Boreoteuthis) borealis has a seven-tooth radula.

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 © 2004 Richard E. Young
About This Page

Richard E. Young

Dept of Oceanography
University of Hawaii
Honolulu, Hawaii 96822

National Marine Fisheries Service
Systematics Laboratory
National Museum of Natural History
Washington, D. C. 20560

Tsunemi Kubodera

National Science Museum, Tokyo, Department of Zoology 3-23-1 Hyakunin-cho, Shinjuku-ku, Tokyo, 169 JAPAN

Citing this page:

Young, Richard E., Vecchione, Michael, and Kubodera, Tsunemi. 2004. Gonatopsis Sasaki, 1920. Version 25 October 2004 (under construction). http://tolweb.org/Gonatopsis/19764/2004.10.25 in The Tree of Life Web Project, http://tolweb.org/

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