N. f. pallescens has occasionally been suggested to be a subspecies of the rufous-capped nunlet (N. ruficapilla) of southern Amazonia.

The nominate subspecies has a very dark chestnut crown and plain brown upperparts, lighter on the rump.

[6] The grey-cheeked nunlet has a somewhat restricted range that extends from central Panama to north-central Colombia.

N. f. stulta is the northernmost subspecies; it is found from central Panama into extreme northwestern Colombia.

[6] The grey-cheeked nunlet's feeding behavior has not been documented, though it has been observed taking a variety of arthropod prey.

"[6] The IUCN has assessed the grey-cheeked nunlet as being of Least Concern, though its population is estimated to be fewer than 50,000 mature individuals and decreasing.

[1] The species is considered uncommon to rare in Panama and generally fairly common in Colombia.