Euler’s Flycatcher is fairly uncommon throughout its large range. In the northern portions of its range, it is a resident of humid lowland forest. Birds from further south are migrants, breeding in the southern extent of their range, then migrating further north for the austral winter. These different patterns are reflected in this species’ several subspecies: two subspecies are migratory, and three additional subspecies are residents. All subspecies share a fairly dark brownish or olive-brown coloration above, a pale belly, and olive or brown on the chest. Additionally, all have buffy wingbars and a vague eyebrow stripe. They occupy dense understory of woodlands and forest edges, where they feed by sallying for insects. They are generally solitary and do not join mixed flocks. Their voice varies by subspecies, but all share a short buzzy quality.