Under Construction
This is an archived version of a Tree of Life page. For up-to-date information, please refer to the current version of this page.

Abraliopsis gilchristi (Robson 1924)

Kotaro Tsuchiya
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: Abraliopsis

Introduction

A. gilchristi is a circum-southern transition species that inhabits waters between 20° - 45° S.

Characteristics

  1. Tentacle clubs
    1. Two rows of distinctly different-sized hooks on manus.
    2. Carpal flap and aboral keel distinct.
      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 the tentacular club of A. gilchristi, South African waters.Drawing from Voss (1967).

  2. Arms
    1. Arms IV relatively long; ALI IV = 40-65.
    2. Arms with 17 - 28 hooks and distal suckers (excl. arm IV).

  3. Hectocotylus and male sexual dimorphism
    1. Hectocotylus with three different-sized offset flaps.
    2. Modified portion with armature.
    3. Spatulate trabeculae develop on the protective membrane of left arm IV.
    4. Oral surface of arms I-III ornamented with numerous small conical papillae.
      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 some arms of A. gilchristi, including the hectocotylized right arm IV. Drawing from Voss (1967).

  4. Integumental Photophores
    1. Ventral mantle with scattered but relatively dense arrangement of integumental organs and distinct mid-ventral photophore-less strip.
    2. Ventral funnel with four stripes of dense integumental organs.
    3. Ventral head with four narrow, longitudinal stripes and some intermediate scattered organs between them.
      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. Side view of the head photophores of A. gilchristi, male, 39 mm ML, South African waters. Drawing from Voss (1967).

Life history

Abundance

Alexeyev (1994) reported the highest abundance and frequency of this species between 40° - 45° S in central southern Pacific.

Maturation

In the central South Pacific, the squids caught in April of 1987 were all immature. In July, stage I of maturity was already absent, while individuals at III and IV stages made up 86% of females and 87% of males. In September, the majority of squids were mature or spent (Alexeyev, 1994).

Feeding habitat

This species feeds on crustaceans, mainly copepods, and to a lesser extent on euphausiids and hyperiids (Alexeyev, 1994).

Distribution

Geographical Distribution

A. gilchristi is distributed in circum-southern temperate waters between 20° - 45° S, but is not known from the southern coast of Australia (Riddell, 1985; Alexeyev, 1994). This species is abundant at the southern border of the Subantarctic frontal zone in the central South Pacific (Alexeyev, 1994) Alexeyev classified this as "peripheral notalian species"

References

Alexeyev, D.O. 1994. New data on the distribution and biology of squids from the southern Pacific. Rutenica, 4:151-166.

Riddell, D.J. 1985. The Enoploteuthidae (Cephalopoda: Oegopsida) of the New Zealand region. Fisheries Reserch Bulletin (NZ), 27:1-52.

Voss, G.L. 1967. Some bathypelagic cephalopods from South African waters. Annals of the South African Museum, 50(5):61-88

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 Abraliopsis gilchristi
Location South African waters, west of Slangkop
Reference Voss, G.L. 1967. Some bathypelagic cephalopods from South African waters. Annals of the South African Museum, 50(5):61-88
Creator C. Stolen via G. L. Voss
Sex Male
View Ventral
Size 39 mm ML
Collection SAM 29729
About This Page


Tokyo University of Fisheries, Tokyo, Japan

All Rights Reserved.

Citing this page:

Tsuchiya, Kotaro. 2009. Abraliopsis gilchristi (Robson 1924). Version 01 August 2009 (under construction). http://tolweb.org/Abraliopsis_gilchristi/19687/2009.08.01 in The Tree of Life Web Project, http://tolweb.org/

edit this page
close box

This page is a Tree of Life Leaf Page.

Each ToL leaf page provides a synopsis of the characteristics of a group of organisms representing a leaf at the tip of the Tree of Life. The major distinction between a leaf and a branch of the Tree of Life is that a leaf cannot generally be further subdivided into 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

Abraliopsis gilchristi

Page Content

articles & notes

collections

people

Explore Other Groups

random page

  go to the Tree of Life home page
top