Complete

Gonatus pyros Young 1972

Tsunemi Kubodera, F. G. Hochberg, and Richard E. Young
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Containing group: Gonatus

Introduction

Gonatus pyros is a small gonatid. A spent female measured 125 mm ML (SBMNH no. 61050). Nesis (1982/87) states that some individuals are known to be up to 160 mm ML. G. pyros is distinctive in being the only gonatid known to possess photophores.

Diagnosis

A Gonatus with ...

Characteristics

  1. Arms
    1. Total of 29-33 hooks and suckers present on proximal half of each arm I-III; squid >34 mm GL with 36-41 suckers on proximal half of each arm IV.
  2. Tentacles
    1. Clubs 20-25% of GL.
    2. Club dactylus with 7-8 irregular series at proximal end, decreasing to 4 series in mid-dactylus.
    3. Club ventral-marginal zone with 3, sometimes 4, series of suckers in central region all nearly same size.
    4. Club dorsal-marginal zone with 3 irregular series dorsal to large central hook.
    5. Club medial zone with large central hook; distal hook present, occasionally joined by an enlarged sucker with a large tooth; proximal series with usually 3-4 small hooks, occasionally preceeded by a series of suckers. Proximal hooks decrease in size toward club base
    6. Total number of suckers (excluding terminal pad and medial zone) on tentacular club: about 151-184.
    7. Median region of tentacular stalk between marginal series with a single, occasionally double and slightly irregular series of sucker adjacent to the ventral-marginal series of the stalk. Lenth variable but usually reaches 3/4 of marginal series length. Medial suckers number between 50-125.
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      Figure. Oral view of the tentacle of G. pyros. Top - Distal region of tentacle, 35? mm GL. Middle - Enlargement of club from top figure. Drawings from Young (1972). Bottom - Distal region of tentacle, 55 mm ML, preserved. Photograph by R. Young.

  3. Head
    1. Beaks.  Descriptions can be found here: Lower beak; upper beak.

  4. Photophores
    1. Large, somewhat oval photophore present on ventral surface of each eye.
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      Figure. Ventral view of the head and eyes of G. pyros showing ocular photophore. Left - Eyelid folded back to reveal photophore, preserved, 55 mm ML, immature female. Insert - Drawing of eye and photophore from Young (1972). Right - Fresh squid with the left eye protruding showing the white ocular photophore. Photograph by T. Kubodera. Note the peculiar surface of the photophore which seems to have many small pores.

Comments

More details of the description of G. pyros can be found here.

Life History

The size of the juvenile at which the various hooks first develop is often distinctive of the species.
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Figure. Chart of the size ranges over which hooks in juveniles of G. pyros first appear. Chart modified from Young (1972).

Distribution

Type locality: 33°37'N, 118°26'W, eastern North Pacific off Southern California. G. pyros is broadly distributed in the central and eastern North Pacific.

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Figure. Distribution of G. pyros. Dark region indicates known range; light areas indicate estimated range. Chart modified from Okutani, et al. (1988).

References

Okutani, T., T. Kubodera and K. Jefferts. 1983. Diversity, distribution and ecology of gonatid squids in the subarctic Pacific: A review. Bull. Ocean Res. Inst., Univ. Tokyo, No. 26 (1):150-192.

Young, R. E. 1972. The systematics and areal distribution of pelagic cephalopods from the seas off Southern California. Smithson. Contr. Zool., 97: 1-159.

Title Illustrations
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Scientific Name Gonatus pyros
Reference Young, R. E. 1972. The systematics and areal distribution of pelagic cephalopods from the seas off Southern California. Smithson. Contr. Zool., 97: 1-159.
View Ventral
Size 39 mm GL
Image Use creative commons This media file is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0.
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About This Page


National Science Museum, Tokyo, Japan

F. G. Hochberg
Santa Barbara Museum of Natural History, Santa Barbara, California, USA


University of Hawaii, Honolulu, HI, USA

Page: Tree of Life Gonatus pyros Young 1972. Authored by Tsunemi Kubodera, F. G. Hochberg, and 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:

Kubodera, Tsunemi, F. G. Hochberg, and Richard E. Young. 2012. Gonatus pyros Young 1972. Version 10 November 2012. http://tolweb.org/Gonatus_pyros/19774/2012.11.10 in The Tree of Life Web Project, http://tolweb.org/

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