GonatopsisTsunemi Kubodera, F. G. Hochberg, Richard E. Young, and Michael Vecchione
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- Hooks in medial two armature series on arms I-III.
- Tentacles absent beyond early juvenile stages.
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.
- Radula with teeth in 5 or 7 series depending on species.
- Mantle tissue muscular or flabby depending on species.
- Fins rhomboid or sagittate in shape depending on species.
- 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||?|
Tentacles are present in paralarvae but are lost at different early stages depending on the species (Nesis, 1973).
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.
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
- First online 25 October 2004
- Content changed 30 May 2006
Citing this page:
Kubodera, Tsunemi, Hochberg, F. G., Young, Richard E., and Vecchione, Michael. 2006. Gonatopsis http://tolweb.org/Gonatopsis/19764/2006.05.30 in The Tree of Life Web Project, http://tolweb.org. Version 30 May 2006 (under construction).