Onykia ingens: Description Continued

1. Tentacles
   1. Carpal locking apparatus with usually 10-11 suckers (range 8-13).
   2. Terminal (distal) club pad with usually 14 small suckers (range 13-18).
      
2. Arms
   1. Arms subequal (2/3 of ML) with arms I shortest and arms III longest.
      
3. Pigmentation
   1. Pale creamy body color (Tsuchiya and Okutani, 1991) or violet flesh-red (Pfeffer, 1912).
      
4. Beaks
   1. Lower beak with "a very broad, thin and undarkened region of chitin to the sides of the jaw angle which quickly dissolves and is lost in beaks acted upon by a predator's digestive juices" (Clarke, 1986).
   2. Lower beak with a long curved crest; short hood close to crest; lateral wall fold usually curved and very thick anteriorly (Clarke, 1986).
   

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   Figure. side view of lower beak of O. ingens with consecutive cross-sections through the crest and lateral wall. Drawing from Clarke (1980).

Comments

Except where noted, this description is from Pfeffer (1912). Clarke (1980) described an unusual beak type as Moroteuthis A, from a  collection of whale stomach contents (see above figure). In 1986 he was able to identify this beak as belonging to Onykia ingens.

References

Clarke, M. R. 1980. Cephalopoda in the diet of sperm whales of the Southern Hemisphere and their bearing on sperm whale biology. Discovery Reports, 37: 1-324.

Clarke, M. R. (editor). 1986. A Handbook for the Identification of Cephalopod Beaks. Clarendon Press, Oxford, U.K. 273 pp.

Pfeffer, G. 1912. Die Cephalopoden der Plankton-Expedition. Ergebnisse  der Plankton-Expedition der Humboldt-Stiftung. 2: 1-815.