Description: The seven star flying squid, Martialia hyadesi, is a Southern Ocean ommastrephid with an oceanic distribution that extends to the edge of the shelves and slopes of continents and islands. Its range is circumpolar and it is generally associated with the Antarctic Polar Frontal Zone. It has been caught in commercial quantities in the Atlantic sector but is only recorded in smaller numbers from the Indian Ocean and Pacific sectors in scientific samples, the gut contents of predators and in mass strandings on island shores. It has only occasionally been found in commercial catches outside the Atlantic sector. In the northern part of its range in the South Atlantic, commercial catches are highly variable and apparently linked to large-scale oceanographic variability. Martialia hyadesi appears to concentrate in frontal areas where characteristics of the bathymetry generate meso-scale oceanographic features. Such concentrations have been observed at shelf breaks and in the deep ocean near a submarine ridge. Predator data confirm the circumpolar distribution of the species and its relationship with the APFZ. Grey-headed albatrosses appear to forage for M. hyadesi in the region of meso-scale oceanographic features associated with the bathymetry of submarine ridges and the shelves of oceanic islands. In the medium future, improved understanding of oceanographic variability of the Southern Ocean may provide the basis for long term forcecasting in a fishery for the species. In the nearer future, improved knowledge of the behaviour of the species in relation to meso-scale oceanography may provide the basis for short-term forecasting of the location of shoals based on remotely sensed images of surface oceanography. The life cycle of M. hyadesi is poorly understood and, in view of increased commercial interest in the species in recent years, and its conservation value in the CCAMLR area, there is a need for more information on the location of spawning and feeding grounds and seasonal migrations.