The purpleback flying squid or purpleback squid (Sthenoteuthis oualaniensis) is a species of cephalopod in the family Ommastrephidae, occurring in the Indo-Pacific. It is considered one of the most abundant large squids.

Sthenoteuthis oualaniensis, or the purpleback squid, is a warm-water oceanic cephalopod mainly distributed in the subtropical and equatorial waters of the Indian and Pacific Oceans, especially abundant in the South China Sea and northwestern Indian Ocean [ 1 ].

Sthenoteuthis oualaniensis, commonly known as tobiika, purpleback flying squid or purple squid (among other names), is thought to be the most abundant large squid in the tropical and subtropical waters of the Indo-Pacific region (Young and Hirota, 1998; Dunning, 1998). Its congener, S. pteropus, replaces S. oualaniensis in the Atlantic Ocean.

The purpleback flying squid (Ommastrephidae: Sthenoteuthis oualaniensis) is an important species at higher trophic levels of the regional marine ecosystem in the South China Sea (SCS), where it is considered to show the potential for fishery development.