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Sthenoteuthis Verrill 1880

Richard E. Young and Michael Vecchione
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taxon links [up-->]Sthenoteuthis oualaniensis [up-->]Sthenoteuthis pteropus [down<--]Ommastrephinae Interpreting the tree
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Containing group: Ommastrephinae


Members of Sthenoteuthis are the dominant ommastrephid squids in tropical waters of the world's oceans and are commonly seen at the ocean's surface at night. They range in size from ca. 100 mm ML to 650 mm ML.

Brief diagnosis:

An ommastrephin with ...



  1. Arms
    1. Arms tips in subadults not unusually attenuate; arms I with 20-30 pairs of suckers.
    2. Hectocotylus with pores. A fully developed pore passes through the protective membrane.
    3. Width of ventral protective membrane of arm III approximately equal to arm width.

  2. Tentacles
    1. Largest club suckers with small pointed teeth and one large pointed tooth in each quadrant.
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    Figure. Oral view of inner ring of largest club sucker of S. oualaniensis. Drawing from Roeleveld (1988).

  3. Funnel/mantle locking-apparatus
    1. Mantle locking-apparatus with anterior bifurcation.

  4. Photophores
    1. Small subcutaneous photophores on ventral surfaces of mantle, head and arms III-IV (see photographs on Ommastrephinae page).
    2. Large, oval, dorsal photophore patch composed of dense aggregaton of subcutaneous photophores on mantle near anterior end.
    3. Luminous patch on ventral surface of each eyeball.
    4. Two photophores on ventral surface of intestine in paralarvae and juveniles.
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    Click on an image to view larger version & data in a new window

    Figure. Dorsal and dorsal-oblique of the dorsal photophore patch in S. oualaniensis with various stages of concealment. Top - Photophore patch (white area) mostly visible. Middle - Photophore patch almost completely concealed by chromatophores. Typically in preserved squid, the patch is not seen due to chromatophore cover. Bottom left - Photophore patch half partially covered and half uncovered. Photographs by R. Young. Bottom right - Cleared and stained portion of the mantle showing the dorsal photophore patch and the tip of the gladius. Scale bar is 3 mm. Photograph from Kishimoto and Kohno (1992).

Comparison of species

 Funnel/mantle locking-apparatus fused
Sthenoteuthis oualaniensis
Sthenoteuthis pteropus


Circumglobal in tropical and subtropical, occasionally in temperate waters. S. oualaniensis is found in Pacific and Indian Ocean waters and S. pteropus in Atlantic Ocean waters.


Kishimoto, H. and H. Kohno. 1992. Development of the luminous organ in the purpleback flying squid, Sthenoteuthis oualaniensis, as shown by Alcian Blue stain techniques. Bull. Inst. Oceanic Res. & Develop., Tokai Univ, 13: 71-83.

Roeleveld, M. A. 1988. Generic interrelationships within the Ommastrephidae (Cephalopoda). P.277-314. In: M. R. Clarke and E. R. Trueman (eds.). The Mollusca. Vol. 12. Paleontology and Neontology of Cephalopods. Academic Press, N.Y., 355pp.

Title Illustrations
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Scientific Name Sthenoteuthis oualaniensis
Location 5 km off Kona, Hawaii at 1942.2'N, 1565'W over bottom depth of 1500m.
Comments S. oualaniensis swimming just below the surface on a calm night (wind SW at 5 kts).
Specimen Condition Live Specimen
Identified By R. E. Young
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Copyright © 2014 Jeffrey Milisen
About This Page

University of Hawaii, Honolulu, HI, USA

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

Page: Tree of Life Sthenoteuthis Verrill 1880. Authored by Richard E. Young and Michael Vecchione. 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. and Michael Vecchione. 2015. Sthenoteuthis Verrill 1880. Version 11 October 2015 (under construction). http://tolweb.org/Sthenoteuthis/19946/2015.10.11 in The Tree of Life Web Project, http://tolweb.org/

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