Discoteuthis
Richard E. YoungThis tree diagram shows the relationships between several groups of organisms.
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close boxIntroduction
Discoteuthis is easily recognized by the large fins, small tentacular clubs and the presence of only suckers on the arms. It is broadly distributed in tropical and subtropical waters of all oceans. These squid have never been observed alive and little is known about their biology or ecology. Discoteuthis sp A could be the mature male of D. discus.
Brief diagnosis:
A cycloteuthid ...
- with large, oval fins that extend the full length of the mantle.
Characteristics
- Tentacles
- Medial suckers on manus of club greatly enlarged.
- Medial suckers on manus of club greatly enlarged.
- Mantle
- Tail absent.
- Tail absent.
- Fins
- Fins large, oval; length equal to ML in subadults.
- Fins large, oval; length equal to ML in subadults.
- Photophores
- Photophore arrangement varies with species. Photophores absent from eyes and viscera.
Comments
The following table compares the four possible species.
Shape of groove of funnel locking-apparatus | Mantle photophores | Head photophores | Brachial crown photophores | Free anterior mantle margin with tissue flaps | Dentition of large manus suckers | |
D. discus | Diagonal | At posteroventral mantle apex | Four ? | None | No | Numerous, small, flattened to rounded teeth |
Discoteuthis sp. A | Diagonal | At posteroventral mantle apex | Four | Series on arms I | No | None. Teeth absent |
Discoteuthis sp. B | V-shaped | ?? | ?? | ?? | ?? | Numerous small, pointed teeth |
D. laciniosa | V-shaped | At anteroventral mantle margin | None | On web between arms III & IV | Yes | Numerous irregular, low scalloped teeth |
References
Young, R. E. and C. F. E. Roper. 1969. A monograph of the Cephalopoda of the North Atlantic: The family Cycloteuthidae. Smithsonian Contributions to Zoology No. 5:1-24.
About This Page
University of Hawaii, Honolulu, HI, USA
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Page: Tree of Life Discoteuthis Authored by . Richard E. Young. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.
Citing this page:
Young, Richard E. 1999. Discoteuthis http://tolweb.org/Discoteuthis/19621/1999.01.01 in The Tree of Life Web Project, http://tolweb.org/
. Version 01 January 1999 (under construction).