Under Construction

Onychoteuthis aequimanus Gabb, 1868

K.S.R. Bolstad
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
Containing group: Onychoteuthis

Introduction

Gabb (1868) described Onychoteuthis aequimanus from two specimens collected near the Society Islands.  Although it was synonymized with Os. banksii by Adam (1962) and Voss (1962), several subsequent authors have recognized the existence of multiple banksii-affiliated species in the Pacific (Young & Harman 1987, Bolstad 2008).  Examination of the syntypes suggests that Os. aequimanus is the correct name for one of these Pacific species.  

Characteristics


Figure. O. cf. aequimanus, in dorsal arm-curl posture, side view (in situ photograph, same squid as in title photograph). Top insert: Enlargement showing gladius rostrum (top yellow arrow) and gladius conus (bottom yellow arrow. Bottom insert: Enlargement of club showing terminal pad of right club (yellow arrow) apparently locked to aboral surface of terminal pad of left club.  © 2016 Jeffrey Milisen

  1. Photophores
    1. Two circular intestinal photophores present. Anterior photophore ~40-60% diameter of posterior photophore.
    2. Ocular photophore a long whitish patch on ventral surface of each eyeball.

  2. Measurements of larger syntype
    1. Mantle length - 93 mm
    2. Arm lengths - 37-50 mm
    3. Fin length - 49 mm
    4. Fin width - 56 mm (damaged)
    5. Club length - 24 mm (right)
    6. Club hook numbers - 23
    7. Largest hooks - Hooks V6 and V7
    8. Smallest mid-series dorsal hooks - Hooks D4 and D5

  3. Tentacle club
    1. Length ~28% ML, with 20–23 hooks.
    2. Distal-most ventral hook bases not produced into spike below ML ~90 mm; may develop small spike at greater MLs.
      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
      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. O. aequimanus, left tentacular club, oral view, female, 70 mm ML. Note the suckers of the terminal pad (see above photograph. ©

    Comments

    Gabb (1868) remarked that the Os. aequimanus syntypes (two males, ANSP 6444) had been long preserved in alcohol before he received them, and had lost much pigmentation. Their soft tissues have also hardened, the tentacles appear stretched, and the hooks somewhat desiccated.  However, most of the important characters (photophores, club morphology overall body proportions, beak and radula) are in reasonable condition.

Life History

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. Growth stages of O. aequimanus, dorsal and ventral views. Top left _ 138 mm ML, female. Top right - 66 mm ML, sex unknown. Bottom left - 37 mm ML, sex unknown. Bottom right - 15 mm ML, sex unknown. ©

Distribution

Pacific Ocean, south of 30°N; known from Hawaiian and New Zealand waters, Palmyra Island, and the Society Islands.

References

Adam, W. 1962. Céphalopodes de l’Archipel du Cap–Vert, de l’Angola et du Mozambique. Memórias da Junta de Investicacões do Ultramar, second series, 33: 9–64, pl. 1.

Bolstad, K.S. 2008. Two new species and a review of the squid genus Onychoteuthis Lichtenstein, 1818 (Oegopsida: Onychoteuthidae) from the Pacific Ocean. Bulletin of Marine Science, 83: 481–529.

Bolstad, K.S.R. 2010. Systematics of the Onychoteuthidae Gray, 1847 (Cephalopoda: Oegopsida). Zootaxa, 2696: 186 pp.

Gabb, W.M. 1868. Description of a new species of cephalopod from the South Pacific. American Journal of Conchology, 4: 23–24, 1 pl.

Voss, G.L. 1962. List of the types and species of cephalopods in the collections of the Academy of Natural Sciences of Philadelphia. Notulae Naturae, 356: 1–7.

Young, R.E. & Harman, R.F. 1987. Descriptions of the larvae of three species of the Onychoteuthis banksii complex from Hawaiian waters. The Veliger, 29: 313–321.

Title Illustrations
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
Scientific Name Onychoteuthis aequimanus
Location Off the Kona Coast, Hawaii Island over bottom depths of about 1500 m.
Comments Squid not captured therefore identification uncertain. Tentative identification, from in situ photographs, based on chromatophore pattern of ventral mantle and minimum length of tentacle clubs.
Specimen Condition Live Specimen
Identified By R. E. Young
Life Cycle Stage Young
View Dorsolateral
Size Unknown
Copyright © 2016 Jeffrey Milisen
About This Page


EOS Research Institute, Auckland University of Technology, New Zealand

Correspondence regarding this page should be directed to K.S.R. Bolstad at

All Rights Reserved.

Citing this page:

Bolstad, K.S.R. 2016. Onychoteuthis aequimanus Gabb, 1868. Version 16 November 2016 (under construction). http://tolweb.org/Onychoteuthis_aequimanus/145219/2016.11.16 in The Tree of Life Web Project, http://tolweb.org/

edit this page
close box

This page is a Tree of Life Branch Page.

Each ToL branch page provides a synopsis of the characteristics of a group of organisms representing a branch of the Tree of Life. The major distinction between a branch and a leaf of the Tree of Life is that each branch can be further subdivided into descendent branches, that is, subgroups representing distinct genetic lineages.

For a more detailed explanation of the different ToL page types, have a look at the Structure of the Tree of Life page.

close box

Onychoteuthis aequimanus

Page Content

articles & notes

collections

people

Explore Other Groups

random page

  go to the Tree of Life home page
top