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Onykia robusta Description

Richard E. Young, Michael Vecchione, and Kotaro Tsuchiya
  1. Arms
    1. Arm IV longest, 90-100% of ML.
    2. Arms I with over 50 pairs of suckers; arms II-IV with 60 pairs of suckers.

  2. Tentacles
    1. Club slender, not expanded
    2. Carpal locking apparatus with 10-12 suckers.
    3. Terminal (distal) club pad with 10-12 small suckers.
    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. Oral view of tentacular club of O. robusta. Drawing from ??

  3. Gladius
    1. Leaf-shaped.
    2. Rostrum 25-40% of GL; opaque, circular in cross-section.
    3. Keel not thickened posteriorly.
    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. Ventral views of the gladius of O. robusta with cross-sections. Top - female, 1630 mm GL. Drawing from Toll (1982). Bottom - 1615 mm ML. Drawing from Sasaki (1929).

  4. Pigmentation
    1. Buccal region unpigmented.
    2. Weak, dark, middorsal chromatophore strip on mantle.


Toll, R.B.  1982.  The comparative morphology of the gladius in the Order Teuthoidea (Mollusca: Cephalopoda) in relation to systematics and phylogeny. PhD. Dissertation, University of Miami, 390 pp.

About This Page

University of Hawaii, Honolulu, HI, USA

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

Tokyo University of Fisheries, Tokyo, Japan

Page: Tree of Life Onykia robusta Description Authored by Richard E. Young, Michael Vecchione, and Kotaro Tsuchiya. 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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Onykia (Onykia) robusta

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