What feature defines the migratory or territorial boundaries of a female *Idiacanthus* in the deep ocean ecosystem?

Specific vertical depth bands defined by temperature and pressure layers

The ecological range or 'territory' of a deep-sea dragonfish differs fundamentally from that of a large coastal predator. While a surface predator might cover thousands of miles across the continental shelf, the deep-sea dragonfish's existence is governed by physical parameters of its environment rather than wide geographical travel. The area inhabited by a female *Idiacanthus* is primarily defined by specific layers of consistent temperature and pressure. This means relatives in disparate horizontal locations, such as off the Juan de Fuca Trench and off the California coast, can share the same ecosystem simply by existing within the same vertical depth band.