Nidulariums are sometimes confused with Neoregelia but they have softer spines and larger bracts separating the flowers.  Most project their inflorescence above the open rosette of leaves and not down in the cup like Neoregelia.

The egg-like flowers nestle in the bracts, giving them their nickname of "birdnest bromeliads".

The name Nidularium is taken from the Latin nidus meaning "nest".