Recent scientific and commercial deepwater trawls provide evidence that the loliginid squid, Loligo gahi occurs much deeper than previously believed. Three immature and maturing squids were caught in two hauls between 528 and 626 m depth, exceeding the previous maximum recorded depth of 400 m. An L. gahi egg mass was found on the bottom attached to polychaete tube sampled from depths of 68–71 m. It represents a new spawning habitat, because before the species was known to spawn only in inshore kelp forests, well off the bottom, at depths <20 m.

Samples of Loligo gahi from the Falkland Islands Interim Conservation and Management Zone collected in March 1987 were analysed to determine the relationships between mass of reproductive and somatic organs during maturation. There was a progressive increase in mass of the reproductive organs with growth in males, while in females these organs did not show a conspicuous increase in mass until a body mass of c. 40 g was reached. No change was found in the mass of the digestive gland in relation to body mass or in the water content of male and female somatic tissues during maturation. Growth of reproductive organs in L. gahi seems to be supported by diet and not at the expense of somatic tissue.

Fifteen specimens of Loligo gahi caught within the Falkland Islands Interim Conservation and Management Zone during March 1988 were subject to genetic analysis using horizontal starch gel electrophoresis. Comparison of allele frequencies at 22 clearly resolving putative enzyme loci showed these animals to exhibit a degree of genetic differentiation from samples of Loligo forbesi and Loligo vulgaris vulgaris (I = 0.19 and 0.22 respectively) greater than that normally expected between congeneric species. The degree of difference was of the order typically exhibited between members of different but confamilial genera, for example as here between Loligo forbesi and Alloteuthis subulata (I = 0.22). It is therefore concluded that Loligo gahi should no longer be regarded as a member of the genus Loligo. Genetic analysis of further species is necessary to clarify whether or not Loligo gahi should, as has been suggested on morphological grounds, be united in a separate genus with other American myopsid species also currently ascribed to the genus Loligo.