Both sexes have a straight bill; the maxilla is blackish and the mandible orange with a dark tip.

[6] Males of the nominate subspecies have a glittering golden- to emerald green central crown and a velvety blackish supercilium.

The upper throat has a glittering violet-blue patch, the breast and belly are dark golden green, and the undertail coverts are greenish with narrow gray and rufous edges.

Females are generally duller, with less iridescence, and do not have the black supercilium or the violet throat patch.

[6] The nominate subspecies of velvet-browed brilliant is found in the highlands and tepuis where Venezuela, Guyana, and Brazil meet.

Subspecies H. x. williardi is found further south, on the tepuis of the southern Venezuela-northern Brazil border.

[1] It is locally abundant, and might be present in unexplored suitable habitat in the gaps among its scattered known locations.