This very large oceanic squid attains a mantle length of up to 2.7 m (Young and Mangold 2008). This species undergoes downward ontogenetic migration. Paralarvae are most abundant in the upper 100 m, larger juveniles occur between ~500 and 600 m, and subadults occur between 440 and 1,200 m (Voss et al.
1992). Statolith growth increment analysis of paralarvae and juvenile statoliths suggest this species has a short life span and fast growth rates prior to migration to deeper waters to mature (Arkhipkin 1996). It is possible that this squid has been observed from Remotely Operated Vehicles, on such occasions when startled it inflates its mantle and squirts ink into the mantle cavity (Young and Mangold 2008). This species is preyed upon by Pacific pomfret, Brama japonica
, and skates.