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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.
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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.
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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.

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.