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Opisthoteuthis depressa: Description Continued

Richard E. Young and Michael Vecchione
  1. Eyes
    1. Large, diameter 1/2 head width.
  2. Funnel
    1. Funnel organ not described.
  3. Fins
    1. Length 1.5-2.0 times width.
  4. Gills
    1. Number of gill lamellae not described.

  5. Optic lobe and nerves
    1. Not described.

  6. Digestive tract
    1. Not described.

  7. Beaks
    1. Not described.

  8. Male and female reproductive system
    1. Not described.

  9. Shell
    1. Nearly straight in young, U-shaped in adults.
    2. Saddle with figure 8 cross-section.
    3. Wings tips conical.
    4. Click on an image to view larger version & data in a new window
      Click on an image to view larger version & data in a new window

      Figure. Shell of O. depressa. A - Posterior view of holotype. B - Posterior view of wing showing cross-section, same shell. C - Dorsal view, adult male. D - Posterior view of wing showing cross-sections, same shell. Drawings from Sasaki, 1929.

  10. Pigmentation
    1. Aboral surfaces deep gray.
    2. Oral surfaces mostly reddish violet.
    3. Lips, cirri, margins of suckers and undersurfaces of fins lighter hue.
    4. Areolae - Pink, mostly in 8 rows. Anterior 4 rows each with 8-9 areolae. Rows begin behind eye prominences and extend forward along mid-aboral surface of arms I and II. Posterior 4 rows each with 8-9 areolae. Rows begin behind fins and extend along mid-aboral surface of arms III and IV. Additional areolae: One on upper surface of funnel; 2 on web near fin bases.
    5. Click on an image to view larger version & data in a new window
      Click on an image to view larger version & data in a new window

      Figure. Aboral view of small (ca. 135 mm max. width) female of O. depressa. Drawing from Sasaki, 1929.

  11. Measurements
    Sex Male Female
    Head width, mm 38 35
    Fin length 18 15
    Fin width 12 10
    Arm I, length 125 100
    Arm II, length 130 104
    Arm III, length 135 110
    Arm IV, length 132 110
    Max. sucker diameter 9-10 2


The above description is taken from Sasaki, 1929.


Sasaki, M. 1929. A monograph of the dibranchiate cephalopods of the Japanese and adjacent waters. Journal of the College of Agriculture, Hokkaido Imperial University, 20(Supplementary number):1-357.

About This Page

University of Hawaii, Honolulu, HI, USA

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

Page: Tree of Life Opisthoteuthis depressa: Description Continued 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.

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